A4 1,8 TS coolant temp reads low
 

Hi all,

My 2001 A4 Avant 1,8 TS (8D chassis, corresponding to B5 saloon, motor
variant AJL) used to have coolant temp at a consistent 90C (is that
192F) during suburban driving, ambient temp between 0C-10C (32F-50F)

About one month ago it started showing coolant temp at a lower temp of
86C (183F).

Oil temp has been and still is consistent at ca. 80C = 175F.

I suspect that either 1) the temperature sensor (mounted on top edge of
head, aft) may be giving a bad reading - or that 2) some thermostatic
valve is stuck, allowing 100% of all coolant to flow throught the
radiator, even if ambient temp is low.

But - on Audiworld I read articles that broken temp sensors tend to
fluctuate wildly, which mine does not do. Mine just reads low. So this
may indicate that I have something else wrong - but what?

Those of you - having a similar experience yourself - who managed to
fix this, can you pls tell me what you did?

Thanks, Robert in Gothenburg Sweden, where we're still waiting for winter.

Re: A4 1,8 TS coolant temp reads low
 

Robert wrote:
> Hi all,
>
> My 2001 A4 Avant 1,8 TS (8D chassis, corresponding to B5 saloon, motor
> variant AJL) used to have coolant temp at a consistent 90C (is that
> 192F) during suburban driving, ambient temp between 0C-10C (32F-50F)
>
> About one month ago it started showing coolant temp at a lower temp of
> 86C (183F).
>
> Oil temp has been and still is consistent at ca. 80C = 175F.
>
> I suspect that either 1) the temperature sensor (mounted on top edge of
> head, aft) may be giving a bad reading - or that 2) some thermostatic
> valve is stuck, allowing 100% of all coolant to flow throught the
> radiator, even if ambient temp is low.
>
> But - on Audiworld I read articles that broken temp sensors tend to
> fluctuate wildly, which mine does not do. Mine just reads low. So this
> may indicate that I have something else wrong - but what?
>
> Those of you - having a similar experience yourself - who managed to
> fix this, can you pls tell me what you did?
>
> Thanks, Robert in Gothenburg Sweden, where we're still waiting for winter.
>

It sounds more like a bad (open) thermostat. They respond to engine temperature
not ambient.

Changing the temp sensor is probably worth a try and is a good idea anyway as
they are prone to failure, easy to change and cheap but the thermostat is more
likely to be the problem.

Changing the thermostat is usually done when the timing belt is changed. It is a
large job and if you chose to do it be sure to have the timing belt and all
associated parts done at the same time. The parts are the cheap part of the job
and it needs to be done on or before scheduled time / distance anyway.

Re: A4 1,8 TS coolant temp reads low
 

Robert wrote:
> Hi all,
>
> My 2001 A4 Avant 1,8 TS (8D chassis, corresponding to B5 saloon, motor
> variant AJL) used to have coolant temp at a consistent 90C (is that
> 192F) during suburban driving, ambient temp between 0C-10C (32F-50F)
>
> About one month ago it started showing coolant temp at a lower temp of
> 86C (183F).
>
> Oil temp has been and still is consistent at ca. 80C = 175F.
>
> I suspect that either 1) the temperature sensor (mounted on top edge of
> head, aft) may be giving a bad reading - or that 2) some thermostatic
> valve is stuck, allowing 100% of all coolant to flow throught the
> radiator, even if ambient temp is low.
>
> But - on Audiworld I read articles that broken temp sensors tend to
> fluctuate wildly, which mine does not do. Mine just reads low. So this
> may indicate that I have something else wrong - but what?
>
> Those of you - having a similar experience yourself - who managed to
> fix this, can you pls tell me what you did?
>
> Thanks, Robert in Gothenburg Sweden, where we're still waiting for winter.
>

It sounds more like a bad (open) thermostat. They respond to engine temperature
not ambient.

Changing the temp sensor is probably worth a try and is a good idea anyway as
they are prone to failure, easy to change and cheap but the thermostat is more
likely to be the problem.

Changing the thermostat is usually done when the timing belt is changed. It is a
large job and if you chose to do it be sure to have the timing belt and all
associated parts done at the same time. The parts are the cheap part of the job
and it needs to be done on or before scheduled time / distance anyway.

Re: A4 1,8 TS coolant temp reads low
 

Robert wrote:
> Hi all,
>
> My 2001 A4 Avant 1,8 TS (8D chassis, corresponding to B5 saloon, motor
> variant AJL) used to have coolant temp at a consistent 90C (is that
> 192F) during suburban driving, ambient temp between 0C-10C (32F-50F)
>
> About one month ago it started showing coolant temp at a lower temp of
> 86C (183F).
>
> Oil temp has been and still is consistent at ca. 80C = 175F.
>
> I suspect that either 1) the temperature sensor (mounted on top edge of
> head, aft) may be giving a bad reading - or that 2) some thermostatic
> valve is stuck, allowing 100% of all coolant to flow throught the
> radiator, even if ambient temp is low.
>
> But - on Audiworld I read articles that broken temp sensors tend to
> fluctuate wildly, which mine does not do. Mine just reads low. So this
> may indicate that I have something else wrong - but what?
>
> Those of you - having a similar experience yourself - who managed to
> fix this, can you pls tell me what you did?
>
> Thanks, Robert in Gothenburg Sweden, where we're still waiting for winter.
>

It sounds more like a bad (open) thermostat. They respond to engine temperature
not ambient.

Changing the temp sensor is probably worth a try and is a good idea anyway as
they are prone to failure, easy to change and cheap but the thermostat is more
likely to be the problem.

Changing the thermostat is usually done when the timing belt is changed. It is a
large job and if you chose to do it be sure to have the timing belt and all
associated parts done at the same time. The parts are the cheap part of the job
and it needs to be done on or before scheduled time / distance anyway.

Re: A4 1,8 TS coolant temp reads low
 

Robert wrote:
> Hi all,
>
> My 2001 A4 Avant 1,8 TS (8D chassis, corresponding to B5 saloon, motor
> variant AJL) used to have coolant temp at a consistent 90C (is that
> 192F) during suburban driving, ambient temp between 0C-10C (32F-50F)
>
> About one month ago it started showing coolant temp at a lower temp of
> 86C (183F).
>
> Oil temp has been and still is consistent at ca. 80C = 175F.
>
> I suspect that either 1) the temperature sensor (mounted on top edge of
> head, aft) may be giving a bad reading - or that 2) some thermostatic
> valve is stuck, allowing 100% of all coolant to flow throught the
> radiator, even if ambient temp is low.
>
> But - on Audiworld I read articles that broken temp sensors tend to
> fluctuate wildly, which mine does not do. Mine just reads low. So this
> may indicate that I have something else wrong - but what?
>
> Those of you - having a similar experience yourself - who managed to
> fix this, can you pls tell me what you did?
>
> Thanks, Robert in Gothenburg Sweden, where we're still waiting for winter.
>

It sounds more like a bad (open) thermostat. They respond to engine temperature
not ambient.

Changing the temp sensor is probably worth a try and is a good idea anyway as
they are prone to failure, easy to change and cheap but the thermostat is more
likely to be the problem.

Changing the thermostat is usually done when the timing belt is changed. It is a
large job and if you chose to do it be sure to have the timing belt and all
associated parts done at the same time. The parts are the cheap part of the job
and it needs to be done on or before scheduled time / distance anyway.

Re: A4 1,8 TS coolant temp reads low
 

TonyJ knastet inn: :

>> Those of you - having a similar experience yourself - who managed to
>> fix this, can you pls tell me what you did?

changed thermostat

>>
>> Thanks, Robert in Gothenburg Sweden, where we're still waiting for
>> winter.
>>
>
> It sounds more like a bad (open) thermostat. They respond to engine
> temperature not ambient.

agree

>
> Changing the temp sensor is probably worth a try and is a good idea
> anyway as they are prone to failure, easy to change and cheap but the
> thermostat is more likely to be the problem.
>
> Changing the thermostat is usually done when the timing belt is changed.

.... when they also (should) change the water pump.

Changing the thermostat, is quite easy - done in 30-60 minutes.

But - changing just the thermostat alone, may be /the last nail in
the coffin/ for the water pump [if it's old], due to a higher
pressure caused by the increased temperature afterwards. And then,
if you have to replace the water pump, replace timing belt as well.


> It is a large job and if you chose to do it be sure to have the timing
> belt and all associated parts done at the same time. The parts are the
> cheap part of the job and it needs to be done on or before scheduled
> time / distance anyway.

Re: A4 1,8 TS coolant temp reads low
 

TonyJ knastet inn: :

>> Those of you - having a similar experience yourself - who managed to
>> fix this, can you pls tell me what you did?

changed thermostat

>>
>> Thanks, Robert in Gothenburg Sweden, where we're still waiting for
>> winter.
>>
>
> It sounds more like a bad (open) thermostat. They respond to engine
> temperature not ambient.

agree

>
> Changing the temp sensor is probably worth a try and is a good idea
> anyway as they are prone to failure, easy to change and cheap but the
> thermostat is more likely to be the problem.
>
> Changing the thermostat is usually done when the timing belt is changed.

.... when they also (should) change the water pump.

Changing the thermostat, is quite easy - done in 30-60 minutes.

But - changing just the thermostat alone, may be /the last nail in
the coffin/ for the water pump [if it's old], due to a higher
pressure caused by the increased temperature afterwards. And then,
if you have to replace the water pump, replace timing belt as well.


> It is a large job and if you chose to do it be sure to have the timing
> belt and all associated parts done at the same time. The parts are the
> cheap part of the job and it needs to be done on or before scheduled
> time / distance anyway.

Re: A4 1,8 TS coolant temp reads low
 

TonyJ knastet inn: :

>> Those of you - having a similar experience yourself - who managed to
>> fix this, can you pls tell me what you did?

changed thermostat

>>
>> Thanks, Robert in Gothenburg Sweden, where we're still waiting for
>> winter.
>>
>
> It sounds more like a bad (open) thermostat. They respond to engine
> temperature not ambient.

agree

>
> Changing the temp sensor is probably worth a try and is a good idea
> anyway as they are prone to failure, easy to change and cheap but the
> thermostat is more likely to be the problem.
>
> Changing the thermostat is usually done when the timing belt is changed.

.... when they also (should) change the water pump.

Changing the thermostat, is quite easy - done in 30-60 minutes.

But - changing just the thermostat alone, may be /the last nail in
the coffin/ for the water pump [if it's old], due to a higher
pressure caused by the increased temperature afterwards. And then,
if you have to replace the water pump, replace timing belt as well.


> It is a large job and if you chose to do it be sure to have the timing
> belt and all associated parts done at the same time. The parts are the
> cheap part of the job and it needs to be done on or before scheduled
> time / distance anyway.

Re: A4 1,8 TS coolant temp reads low
 

TonyJ knastet inn: :

>> Those of you - having a similar experience yourself - who managed to
>> fix this, can you pls tell me what you did?

changed thermostat

>>
>> Thanks, Robert in Gothenburg Sweden, where we're still waiting for
>> winter.
>>
>
> It sounds more like a bad (open) thermostat. They respond to engine
> temperature not ambient.

agree

>
> Changing the temp sensor is probably worth a try and is a good idea
> anyway as they are prone to failure, easy to change and cheap but the
> thermostat is more likely to be the problem.
>
> Changing the thermostat is usually done when the timing belt is changed.

.... when they also (should) change the water pump.

Changing the thermostat, is quite easy - done in 30-60 minutes.

But - changing just the thermostat alone, may be /the last nail in
the coffin/ for the water pump [if it's old], due to a higher
pressure caused by the increased temperature afterwards. And then,
if you have to replace the water pump, replace timing belt as well.


> It is a large job and if you chose to do it be sure to have the timing
> belt and all associated parts done at the same time. The parts are the
> cheap part of the job and it needs to be done on or before scheduled
> time / distance anyway.

Re: A4 1,8 TS coolant temp reads low
 

Frank wrote:
> TonyJ knastet inn: :
>
>>> Those of you - having a similar experience yourself - who managed to
>>> fix this, can you pls tell me what you did?
>
>
> changed thermostat
>
>>>
>>> Thanks, Robert in Gothenburg Sweden, where we're still waiting for
>>> winter.
>>>
>>
>> It sounds more like a bad (open) thermostat. They respond to engine
>> temperature not ambient.
>
>
> agree
>
>>
>> Changing the temp sensor is probably worth a try and is a good idea
>> anyway as they are prone to failure, easy to change and cheap but the
>> thermostat is more likely to be the problem.
>>
>> Changing the thermostat is usually done when the timing belt is changed.
>
>
> ... when they also (should) change the water pump.
>
> Changing the thermostat, is quite easy - done in 30-60 minutes.
>
> But - changing just the thermostat alone, may be /the last nail in
> the coffin/ for the water pump [if it's old], due to a higher
> pressure caused by the increased temperature afterwards. And then,
> if you have to replace the water pump, replace timing belt as well.
>
>
>> It is a large job and if you chose to do it be sure to have the timing
>> belt and all associated parts done at the same time. The parts are the
>> cheap part of the job and it needs to be done on or before scheduled
>> time / distance anyway.
>
>

Thanks guys,

I will indeed change the temp sensor.

As far as water pump goes, I am told by my Audi indy that the water pump
on my motor variant (AJL) is *not* driven off of the timing belt, though
it seems to be a universal truth on this forum that all water pumps are.

My timing belt was changed one year ago at 110 000 km and I find myself
sleeping better at night as a result.

. . . I will nonetheless be left with a more weird problem, that the
car is very hard to start about 10-30 mins after shutoff, requiring the
starter motor to spin for ca. 15 sec before the motor starts . . . more
in another thread I will start shortly.

Cheers, Robert

Re: A4 1,8 TS coolant temp reads low
 

Frank wrote:
> TonyJ knastet inn: :
>
>>> Those of you - having a similar experience yourself - who managed to
>>> fix this, can you pls tell me what you did?
>
>
> changed thermostat
>
>>>
>>> Thanks, Robert in Gothenburg Sweden, where we're still waiting for
>>> winter.
>>>
>>
>> It sounds more like a bad (open) thermostat. They respond to engine
>> temperature not ambient.
>
>
> agree
>
>>
>> Changing the temp sensor is probably worth a try and is a good idea
>> anyway as they are prone to failure, easy to change and cheap but the
>> thermostat is more likely to be the problem.
>>
>> Changing the thermostat is usually done when the timing belt is changed.
>
>
> ... when they also (should) change the water pump.
>
> Changing the thermostat, is quite easy - done in 30-60 minutes.
>
> But - changing just the thermostat alone, may be /the last nail in
> the coffin/ for the water pump [if it's old], due to a higher
> pressure caused by the increased temperature afterwards. And then,
> if you have to replace the water pump, replace timing belt as well.
>
>
>> It is a large job and if you chose to do it be sure to have the timing
>> belt and all associated parts done at the same time. The parts are the
>> cheap part of the job and it needs to be done on or before scheduled
>> time / distance anyway.
>
>

Thanks guys,

I will indeed change the temp sensor.

As far as water pump goes, I am told by my Audi indy that the water pump
on my motor variant (AJL) is *not* driven off of the timing belt, though
it seems to be a universal truth on this forum that all water pumps are.

My timing belt was changed one year ago at 110 000 km and I find myself
sleeping better at night as a result.

. . . I will nonetheless be left with a more weird problem, that the
car is very hard to start about 10-30 mins after shutoff, requiring the
starter motor to spin for ca. 15 sec before the motor starts . . . more
in another thread I will start shortly.

Cheers, Robert

Re: A4 1,8 TS coolant temp reads low
 

Frank wrote:
> TonyJ knastet inn: :
>
>>> Those of you - having a similar experience yourself - who managed to
>>> fix this, can you pls tell me what you did?
>
>
> changed thermostat
>
>>>
>>> Thanks, Robert in Gothenburg Sweden, where we're still waiting for
>>> winter.
>>>
>>
>> It sounds more like a bad (open) thermostat. They respond to engine
>> temperature not ambient.
>
>
> agree
>
>>
>> Changing the temp sensor is probably worth a try and is a good idea
>> anyway as they are prone to failure, easy to change and cheap but the
>> thermostat is more likely to be the problem.
>>
>> Changing the thermostat is usually done when the timing belt is changed.
>
>
> ... when they also (should) change the water pump.
>
> Changing the thermostat, is quite easy - done in 30-60 minutes.
>
> But - changing just the thermostat alone, may be /the last nail in
> the coffin/ for the water pump [if it's old], due to a higher
> pressure caused by the increased temperature afterwards. And then,
> if you have to replace the water pump, replace timing belt as well.
>
>
>> It is a large job and if you chose to do it be sure to have the timing
>> belt and all associated parts done at the same time. The parts are the
>> cheap part of the job and it needs to be done on or before scheduled
>> time / distance anyway.
>
>

Thanks guys,

I will indeed change the temp sensor.

As far as water pump goes, I am told by my Audi indy that the water pump
on my motor variant (AJL) is *not* driven off of the timing belt, though
it seems to be a universal truth on this forum that all water pumps are.

My timing belt was changed one year ago at 110 000 km and I find myself
sleeping better at night as a result.

. . . I will nonetheless be left with a more weird problem, that the
car is very hard to start about 10-30 mins after shutoff, requiring the
starter motor to spin for ca. 15 sec before the motor starts . . . more
in another thread I will start shortly.

Cheers, Robert

Re: A4 1,8 TS coolant temp reads low
 

Frank wrote:
> TonyJ knastet inn: :
>
>>> Those of you - having a similar experience yourself - who managed to
>>> fix this, can you pls tell me what you did?
>
>
> changed thermostat
>
>>>
>>> Thanks, Robert in Gothenburg Sweden, where we're still waiting for
>>> winter.
>>>
>>
>> It sounds more like a bad (open) thermostat. They respond to engine
>> temperature not ambient.
>
>
> agree
>
>>
>> Changing the temp sensor is probably worth a try and is a good idea
>> anyway as they are prone to failure, easy to change and cheap but the
>> thermostat is more likely to be the problem.
>>
>> Changing the thermostat is usually done when the timing belt is changed.
>
>
> ... when they also (should) change the water pump.
>
> Changing the thermostat, is quite easy - done in 30-60 minutes.
>
> But - changing just the thermostat alone, may be /the last nail in
> the coffin/ for the water pump [if it's old], due to a higher
> pressure caused by the increased temperature afterwards. And then,
> if you have to replace the water pump, replace timing belt as well.
>
>
>> It is a large job and if you chose to do it be sure to have the timing
>> belt and all associated parts done at the same time. The parts are the
>> cheap part of the job and it needs to be done on or before scheduled
>> time / distance anyway.
>
>

Thanks guys,

I will indeed change the temp sensor.

As far as water pump goes, I am told by my Audi indy that the water pump
on my motor variant (AJL) is *not* driven off of the timing belt, though
it seems to be a universal truth on this forum that all water pumps are.

My timing belt was changed one year ago at 110 000 km and I find myself
sleeping better at night as a result.

. . . I will nonetheless be left with a more weird problem, that the
car is very hard to start about 10-30 mins after shutoff, requiring the
starter motor to spin for ca. 15 sec before the motor starts . . . more
in another thread I will start shortly.

Cheers, Robert

Re: A4 1,8 TS coolant temp reads low
 

On Sat, 20 Jan 2007 16:08:35 GMT, Robert <rxobert.bxrown@txripnet.se> wrote:
>
>Thanks guys,
>
>I will indeed change the temp sensor.
>
>As far as water pump goes, I am told by my Audi indy that the water pump
>on my motor variant (AJL) is *not* driven off of the timing belt, though
>it seems to be a universal truth on this forum that all water pumps are.
>
>My timing belt was changed one year ago at 110 000 km and I find myself
>sleeping better at night as a result.
>
> . . . I will nonetheless be left with a more weird problem, that the
>car is very hard to start about 10-30 mins after shutoff, requiring the
>starter motor to spin for ca. 15 sec before the motor starts . . . more
>in another thread I will start shortly.
>
>Cheers, Robert

True - your water pump is driven by a small belt taken from the power steering
pump - which is spun by the big ribbed belt...

/daytripper
'00 s4 6spd

Re: A4 1,8 TS coolant temp reads low
 

On Sat, 20 Jan 2007 16:08:35 GMT, Robert <rxobert.bxrown@txripnet.se> wrote:
>
>Thanks guys,
>
>I will indeed change the temp sensor.
>
>As far as water pump goes, I am told by my Audi indy that the water pump
>on my motor variant (AJL) is *not* driven off of the timing belt, though
>it seems to be a universal truth on this forum that all water pumps are.
>
>My timing belt was changed one year ago at 110 000 km and I find myself
>sleeping better at night as a result.
>
> . . . I will nonetheless be left with a more weird problem, that the
>car is very hard to start about 10-30 mins after shutoff, requiring the
>starter motor to spin for ca. 15 sec before the motor starts . . . more
>in another thread I will start shortly.
>
>Cheers, Robert

True - your water pump is driven by a small belt taken from the power steering
pump - which is spun by the big ribbed belt...

/daytripper
'00 s4 6spd

Re: A4 1,8 TS coolant temp reads low
 

On Sat, 20 Jan 2007 16:08:35 GMT, Robert <rxobert.bxrown@txripnet.se> wrote:
>
>Thanks guys,
>
>I will indeed change the temp sensor.
>
>As far as water pump goes, I am told by my Audi indy that the water pump
>on my motor variant (AJL) is *not* driven off of the timing belt, though
>it seems to be a universal truth on this forum that all water pumps are.
>
>My timing belt was changed one year ago at 110 000 km and I find myself
>sleeping better at night as a result.
>
> . . . I will nonetheless be left with a more weird problem, that the
>car is very hard to start about 10-30 mins after shutoff, requiring the
>starter motor to spin for ca. 15 sec before the motor starts . . . more
>in another thread I will start shortly.
>
>Cheers, Robert

True - your water pump is driven by a small belt taken from the power steering
pump - which is spun by the big ribbed belt...

/daytripper
'00 s4 6spd

Re: A4 1,8 TS coolant temp reads low
 

On Sat, 20 Jan 2007 16:08:35 GMT, Robert <rxobert.bxrown@txripnet.se> wrote:
>
>Thanks guys,
>
>I will indeed change the temp sensor.
>
>As far as water pump goes, I am told by my Audi indy that the water pump
>on my motor variant (AJL) is *not* driven off of the timing belt, though
>it seems to be a universal truth on this forum that all water pumps are.
>
>My timing belt was changed one year ago at 110 000 km and I find myself
>sleeping better at night as a result.
>
> . . . I will nonetheless be left with a more weird problem, that the
>car is very hard to start about 10-30 mins after shutoff, requiring the
>starter motor to spin for ca. 15 sec before the motor starts . . . more
>in another thread I will start shortly.
>
>Cheers, Robert

True - your water pump is driven by a small belt taken from the power steering
pump - which is spun by the big ribbed belt...

/daytripper
'00 s4 6spd

Re: A4 1,8 TS coolant temp reads low
 

Robert knastet inn: :
> Frank wrote:

> As far as water pump goes, I am told by my Audi indy that the water pump
> on my motor variant (AJL) is *not* driven off of the timing belt, though
> it seems to be a universal truth on this forum that all water pumps are.


That was not the point ...

To replace the water pump _or_ the timing belt, 90% of the
job is done - replacing the other one as well. The thumb
rule - is to change both at the same time, to save work hours

Re: A4 1,8 TS coolant temp reads low
 

Robert knastet inn: :
> Frank wrote:

> As far as water pump goes, I am told by my Audi indy that the water pump
> on my motor variant (AJL) is *not* driven off of the timing belt, though
> it seems to be a universal truth on this forum that all water pumps are.


That was not the point ...

To replace the water pump _or_ the timing belt, 90% of the
job is done - replacing the other one as well. The thumb
rule - is to change both at the same time, to save work hours

Re: A4 1,8 TS coolant temp reads low
 

Robert knastet inn: :
> Frank wrote:

> As far as water pump goes, I am told by my Audi indy that the water pump
> on my motor variant (AJL) is *not* driven off of the timing belt, though
> it seems to be a universal truth on this forum that all water pumps are.


That was not the point ...

To replace the water pump _or_ the timing belt, 90% of the
job is done - replacing the other one as well. The thumb
rule - is to change both at the same time, to save work hours

Re: A4 1,8 TS coolant temp reads low
 

Robert knastet inn: :
> Frank wrote:

> As far as water pump goes, I am told by my Audi indy that the water pump
> on my motor variant (AJL) is *not* driven off of the timing belt, though
> it seems to be a universal truth on this forum that all water pumps are.


That was not the point ...

To replace the water pump _or_ the timing belt, 90% of the
job is done - replacing the other one as well. The thumb
rule - is to change both at the same time, to save work hours

Re: A4 1,8 TS coolant temp reads low
 

Change the timing belt, water pump and any idler bearings while replacing
one or the other. Sometimes it is considered "Preventative Maintenance".
Kinda like if you need to replace the clutch...........change the rear
crankshaft seal and pilot bearing too!

AFAIK that has been the rule since the Audi 5000, although the rule is
stronger when the timing belt and interference engine could be damaged by a
damaged water pump. :-)

Some Audis, like my 4000S with the 4 cylinder, that rule is NA! :-)

JMHO
later,
dave
(One out of many daves)


"Frank" <NoSpam2Me@online.no> wrote in message
news:51i9bbF1k34bmU1@mid.individual.net...
> Robert knastet inn: :
>> Frank wrote:
>
>> As far as water pump goes, I am told by my Audi indy that the water pump
>> on my motor variant (AJL) is *not* driven off of the timing belt, though
>> it seems to be a universal truth on this forum that all water pumps are.
>
>
> That was not the point ...
>
> To replace the water pump _or_ the timing belt, 90% of the
> job is done - replacing the other one as well. The thumb
> rule - is to change both at the same time, to save work hours

Re: A4 1,8 TS coolant temp reads low
 

Change the timing belt, water pump and any idler bearings while replacing
one or the other. Sometimes it is considered "Preventative Maintenance".
Kinda like if you need to replace the clutch...........change the rear
crankshaft seal and pilot bearing too!

AFAIK that has been the rule since the Audi 5000, although the rule is
stronger when the timing belt and interference engine could be damaged by a
damaged water pump. :-)

Some Audis, like my 4000S with the 4 cylinder, that rule is NA! :-)

JMHO
later,
dave
(One out of many daves)


"Frank" <NoSpam2Me@online.no> wrote in message
news:51i9bbF1k34bmU1@mid.individual.net...
> Robert knastet inn: :
>> Frank wrote:
>
>> As far as water pump goes, I am told by my Audi indy that the water pump
>> on my motor variant (AJL) is *not* driven off of the timing belt, though
>> it seems to be a universal truth on this forum that all water pumps are.
>
>
> That was not the point ...
>
> To replace the water pump _or_ the timing belt, 90% of the
> job is done - replacing the other one as well. The thumb
> rule - is to change both at the same time, to save work hours

Re: A4 1,8 TS coolant temp reads low
 

Change the timing belt, water pump and any idler bearings while replacing
one or the other. Sometimes it is considered "Preventative Maintenance".
Kinda like if you need to replace the clutch...........change the rear
crankshaft seal and pilot bearing too!

AFAIK that has been the rule since the Audi 5000, although the rule is
stronger when the timing belt and interference engine could be damaged by a
damaged water pump. :-)

Some Audis, like my 4000S with the 4 cylinder, that rule is NA! :-)

JMHO
later,
dave
(One out of many daves)


"Frank" <NoSpam2Me@online.no> wrote in message
news:51i9bbF1k34bmU1@mid.individual.net...
> Robert knastet inn: :
>> Frank wrote:
>
>> As far as water pump goes, I am told by my Audi indy that the water pump
>> on my motor variant (AJL) is *not* driven off of the timing belt, though
>> it seems to be a universal truth on this forum that all water pumps are.
>
>
> That was not the point ...
>
> To replace the water pump _or_ the timing belt, 90% of the
> job is done - replacing the other one as well. The thumb
> rule - is to change both at the same time, to save work hours

Re: A4 1,8 TS coolant temp reads low
 

Change the timing belt, water pump and any idler bearings while replacing
one or the other. Sometimes it is considered "Preventative Maintenance".
Kinda like if you need to replace the clutch...........change the rear
crankshaft seal and pilot bearing too!

AFAIK that has been the rule since the Audi 5000, although the rule is
stronger when the timing belt and interference engine could be damaged by a
damaged water pump. :-)

Some Audis, like my 4000S with the 4 cylinder, that rule is NA! :-)

JMHO
later,
dave
(One out of many daves)


"Frank" <NoSpam2Me@online.no> wrote in message
news:51i9bbF1k34bmU1@mid.individual.net...
> Robert knastet inn: :
>> Frank wrote:
>
>> As far as water pump goes, I am told by my Audi indy that the water pump
>> on my motor variant (AJL) is *not* driven off of the timing belt, though
>> it seems to be a universal truth on this forum that all water pumps are.
>
>
> That was not the point ...
>
> To replace the water pump _or_ the timing belt, 90% of the
> job is done - replacing the other one as well. The thumb
> rule - is to change both at the same time, to save work hours

Re: A4 1,8 TS coolant temp reads low
 

I just ran into the same exact problem on the same application. It was
the thermostat.I picked up the part at the dealer.If you are not
mechanically inclined do not attempt to replace it.It has a plastic
housing and is behind the alternator and steering pump.It also has a
sensor on the housing.I went through the same thing replacing the green
sensor,it was not the problem.when i removed the whole housing and took it
apart i found that the plastic tabs that held the thermostat in place broke
off which caused the thermostat to remain open.I purchased the whole
housing,it came with everthing that i needed,it was a little over a $100
but worth it.replaced it and problem resolved.

Re: A4 1,8 TS coolant temp reads low
 

I just ran into the same exact problem on the same application. It was
the thermostat.I picked up the part at the dealer.If you are not
mechanically inclined do not attempt to replace it.It has a plastic
housing and is behind the alternator and steering pump.It also has a
sensor on the housing.I went through the same thing replacing the green
sensor,it was not the problem.when i removed the whole housing and took it
apart i found that the plastic tabs that held the thermostat in place broke
off which caused the thermostat to remain open.I purchased the whole
housing,it came with everthing that i needed,it was a little over a $100
but worth it.replaced it and problem resolved.

Re: A4 1,8 TS coolant temp reads low
 

I just ran into the same exact problem on the same application. It was
the thermostat.I picked up the part at the dealer.If you are not
mechanically inclined do not attempt to replace it.It has a plastic
housing and is behind the alternator and steering pump.It also has a
sensor on the housing.I went through the same thing replacing the green
sensor,it was not the problem.when i removed the whole housing and took it
apart i found that the plastic tabs that held the thermostat in place broke
off which caused the thermostat to remain open.I purchased the whole
housing,it came with everthing that i needed,it was a little over a $100
but worth it.replaced it and problem resolved.

Re: A4 1,8 TS coolant temp reads low
 

I just ran into the same exact problem on the same application. It was
the thermostat.I picked up the part at the dealer.If you are not
mechanically inclined do not attempt to replace it.It has a plastic
housing and is behind the alternator and steering pump.It also has a
sensor on the housing.I went through the same thing replacing the green
sensor,it was not the problem.when i removed the whole housing and took it
apart i found that the plastic tabs that held the thermostat in place broke
off which caused the thermostat to remain open.I purchased the whole
housing,it came with everthing that i needed,it was a little over a $100
but worth it.replaced it and problem resolved.

Re: A4 1,8 TS coolant temp reads low
 

moparmadman wrote:
> I just ran into the same exact problem on the same application. It was
> the thermostat.I picked up the part at the dealer.If you are not
> mechanically inclined do not attempt to replace it.It has a plastic
> housing and is behind the alternator and steering pump.It also has a
> sensor on the housing.I went through the same thing replacing the green
> sensor,it was not the problem.when i removed the whole housing and took it
> apart i found that the plastic tabs that held the thermostat in place broke
> off which caused the thermostat to remain open.I purchased the whole
> housing,it came with everthing that i needed,it was a little over a $100
> but worth it.replaced it and problem resolved.
>
>

Thanks for this good info. I have just replaced the temp sensor but I
notice that the temp is now only a couple of degrees higher, so it may
indeed be a sticking thermostat.

Some questions:

1) was your only problem a low temperature or did you have other
symptoms that caused you to want to replace the thermostat?

2) did you have to remove more than the undertray to get to the pump, or
did you also have to remove the cowling around the timing belt?

3) were the plastic tabs broken through general wear and age, or did
they get broken as a result of your dismantling job?

4) Can you say more about this sensor on the housing - I cannot see one
in the pics on the Haynes manual, but their material is incomplete as a
matter of course.

Grateful for any additional info you can provide.

Thanks, Robert

Re: A4 1,8 TS coolant temp reads low
 

moparmadman wrote:
> I just ran into the same exact problem on the same application. It was
> the thermostat.I picked up the part at the dealer.If you are not
> mechanically inclined do not attempt to replace it.It has a plastic
> housing and is behind the alternator and steering pump.It also has a
> sensor on the housing.I went through the same thing replacing the green
> sensor,it was not the problem.when i removed the whole housing and took it
> apart i found that the plastic tabs that held the thermostat in place broke
> off which caused the thermostat to remain open.I purchased the whole
> housing,it came with everthing that i needed,it was a little over a $100
> but worth it.replaced it and problem resolved.
>
>

Thanks for this good info. I have just replaced the temp sensor but I
notice that the temp is now only a couple of degrees higher, so it may
indeed be a sticking thermostat.

Some questions:

1) was your only problem a low temperature or did you have other
symptoms that caused you to want to replace the thermostat?

2) did you have to remove more than the undertray to get to the pump, or
did you also have to remove the cowling around the timing belt?

3) were the plastic tabs broken through general wear and age, or did
they get broken as a result of your dismantling job?

4) Can you say more about this sensor on the housing - I cannot see one
in the pics on the Haynes manual, but their material is incomplete as a
matter of course.

Grateful for any additional info you can provide.

Thanks, Robert

Re: A4 1,8 TS coolant temp reads low
 

moparmadman wrote:
> I just ran into the same exact problem on the same application. It was
> the thermostat.I picked up the part at the dealer.If you are not
> mechanically inclined do not attempt to replace it.It has a plastic
> housing and is behind the alternator and steering pump.It also has a
> sensor on the housing.I went through the same thing replacing the green
> sensor,it was not the problem.when i removed the whole housing and took it
> apart i found that the plastic tabs that held the thermostat in place broke
> off which caused the thermostat to remain open.I purchased the whole
> housing,it came with everthing that i needed,it was a little over a $100
> but worth it.replaced it and problem resolved.
>
>

Thanks for this good info. I have just replaced the temp sensor but I
notice that the temp is now only a couple of degrees higher, so it may
indeed be a sticking thermostat.

Some questions:

1) was your only problem a low temperature or did you have other
symptoms that caused you to want to replace the thermostat?

2) did you have to remove more than the undertray to get to the pump, or
did you also have to remove the cowling around the timing belt?

3) were the plastic tabs broken through general wear and age, or did
they get broken as a result of your dismantling job?

4) Can you say more about this sensor on the housing - I cannot see one
in the pics on the Haynes manual, but their material is incomplete as a
matter of course.

Grateful for any additional info you can provide.

Thanks, Robert

Re: A4 1,8 TS coolant temp reads low
 

moparmadman wrote:
> I just ran into the same exact problem on the same application. It was
> the thermostat.I picked up the part at the dealer.If you are not
> mechanically inclined do not attempt to replace it.It has a plastic
> housing and is behind the alternator and steering pump.It also has a
> sensor on the housing.I went through the same thing replacing the green
> sensor,it was not the problem.when i removed the whole housing and took it
> apart i found that the plastic tabs that held the thermostat in place broke
> off which caused the thermostat to remain open.I purchased the whole
> housing,it came with everthing that i needed,it was a little over a $100
> but worth it.replaced it and problem resolved.
>
>

Thanks for this good info. I have just replaced the temp sensor but I
notice that the temp is now only a couple of degrees higher, so it may
indeed be a sticking thermostat.

Some questions:

1) was your only problem a low temperature or did you have other
symptoms that caused you to want to replace the thermostat?

2) did you have to remove more than the undertray to get to the pump, or
did you also have to remove the cowling around the timing belt?

3) were the plastic tabs broken through general wear and age, or did
they get broken as a result of your dismantling job?

4) Can you say more about this sensor on the housing - I cannot see one
in the pics on the Haynes manual, but their material is incomplete as a
matter of course.

Grateful for any additional info you can provide.

Thanks, Robert

Re: A4 1,8 TS coolant temp reads low
 

1.yes low temp was the only problem.
2.the thermostat was not near the pump or the timibelt area,it was
behind the power steering pump.if you follow the lower radiator hose from
the bottom up it leads to the plastic housing that bolts to the
block,inside it is the thermostat.
3.it was wear and age.dont forget the housing is plastic.and gets very
hot and cools down constantly.
4.if you get the thermostat from the dealer the
sensor is on the housing.

hopefully this helps.

Re: A4 1,8 TS coolant temp reads low
 

1.yes low temp was the only problem.
2.the thermostat was not near the pump or the timibelt area,it was
behind the power steering pump.if you follow the lower radiator hose from
the bottom up it leads to the plastic housing that bolts to the
block,inside it is the thermostat.
3.it was wear and age.dont forget the housing is plastic.and gets very
hot and cools down constantly.
4.if you get the thermostat from the dealer the
sensor is on the housing.

hopefully this helps.

Re: A4 1,8 TS coolant temp reads low
 

1.yes low temp was the only problem.
2.the thermostat was not near the pump or the timibelt area,it was
behind the power steering pump.if you follow the lower radiator hose from
the bottom up it leads to the plastic housing that bolts to the
block,inside it is the thermostat.
3.it was wear and age.dont forget the housing is plastic.and gets very
hot and cools down constantly.
4.if you get the thermostat from the dealer the
sensor is on the housing.

hopefully this helps.

Re: A4 1,8 TS coolant temp reads low
 

1.yes low temp was the only problem.
2.the thermostat was not near the pump or the timibelt area,it was
behind the power steering pump.if you follow the lower radiator hose from
the bottom up it leads to the plastic housing that bolts to the
block,inside it is the thermostat.
3.it was wear and age.dont forget the housing is plastic.and gets very
hot and cools down constantly.
4.if you get the thermostat from the dealer the
sensor is on the housing.

hopefully this helps.

Re: A4 1,8 TS coolant temp reads low
 

moparmadman wrote:
> 1.yes low temp was the only problem.
> 2.the thermostat was not near the pump or the timibelt area,it was
> behind the power steering pump.if you follow the lower radiator hose from
> the bottom up it leads to the plastic housing that bolts to the
> block,inside it is the thermostat.
> 3.it was wear and age.dont forget the housing is plastic.and gets very
> hot and cools down constantly.
> 4.if you get the thermostat from the dealer the
> sensor is on the housing.
>
> hopefully this helps.
>

Yes thanks, that's a useful set of answers. I think I'll go buy a
thermostat in the next week or so, and try to make do with the existing
housing.

Cheers, Robert

Re: A4 1,8 TS coolant temp reads low
 

moparmadman wrote:
> 1.yes low temp was the only problem.
> 2.the thermostat was not near the pump or the timibelt area,it was
> behind the power steering pump.if you follow the lower radiator hose from
> the bottom up it leads to the plastic housing that bolts to the
> block,inside it is the thermostat.
> 3.it was wear and age.dont forget the housing is plastic.and gets very
> hot and cools down constantly.
> 4.if you get the thermostat from the dealer the
> sensor is on the housing.
>
> hopefully this helps.
>

Yes thanks, that's a useful set of answers. I think I'll go buy a
thermostat in the next week or so, and try to make do with the existing
housing.

Cheers, Robert

Re: A4 1,8 TS coolant temp reads low
 

moparmadman wrote:
> 1.yes low temp was the only problem.
> 2.the thermostat was not near the pump or the timibelt area,it was
> behind the power steering pump.if you follow the lower radiator hose from
> the bottom up it leads to the plastic housing that bolts to the
> block,inside it is the thermostat.
> 3.it was wear and age.dont forget the housing is plastic.and gets very
> hot and cools down constantly.
> 4.if you get the thermostat from the dealer the
> sensor is on the housing.
>
> hopefully this helps.
>

Yes thanks, that's a useful set of answers. I think I'll go buy a
thermostat in the next week or so, and try to make do with the existing
housing.

Cheers, Robert