anon

excellent information christoph, thanks a million for your reply, it
certainly explains a lot.
very much appreciated.
regards.
steve.

"Christoph Bollig" <laserpower@gmx.net> wrote in message
news:q0nqu0lomurj0i26hv2e3d1jp4kc677qbe@4ax.com...
> Hi steve,
>
> > car: audi 80 2.0ltr 16v 1991
> > can anyone tell me what it means when the oil light comes on and beeps
at
> > the same time, i have tried shorting the oil pressure switches to earth
> > which activates the oil light, but no beep, there is plenty of oil in
the
> > engine so i'm figguring it cant be a low level warning lamp.
> > it tends to come on and beep at about 2500 rpm.
> > any advice welcome.
>
> In brief: get the pressure checked as soon as possible. I had a
> similar problem and wrecked my engine by not taking it serious.
>
> What happened was the following (from memory, I might confuse the
> switches):
>
> The Audi 100, 1989 I have has two pressure switches, one is closed at
> no pressure and opens at ~0.3 bar , the other one open at no pressure
> and closes at ~1.8 bar. The auto-check system checks both, but at low
> refs only gives a warning when the pressure is below 0.3 bar. It only
> checks the second switch at somewhere around 2800 rpm. It also checks
> the switches when the engine is not running and gives a warning if
> they don't show zero pressure.
>
> On mine, the low-pressure switch had bad contacts, so that it was
> always "open". I think it had around 10 Ohm when "closed", but that
> was enough for the auto-check to regard it as open. It always gave a
> warning when I turned the ignition before I started the engine, but
> since I was used to have the oil lamp on before the engine starts, I
> didn't pay attention (it was already like this when I got the car).
> Therefore, the system never detected a fault on the 0.3bar switch. At
> some stage, I got oil warnings at around 100km/h. When I reduced the
> speed, the warning was gone again. That was basically the 1.8bar
> switch. The problem disappeared again and came back half a year later.
> By the time I got a proper pressure check, it was too late.
>
> In essence:
>
> - If the autocheck system gives you a warning before you start the
> engine, one of the switches might be faulty.
>
> - Put a DMM on the switch to measure resistance. One of the should
> change immediately when you start the engine. The other one should
> change before you reach 2500 rpm, better much lower.
>
> - Replace the switches, if they don't change properly.
>
> - I would say have the pressure check, if in any doubt.
>
> Christoph
>
> --
> Important: Emails sent to me which contain my full name
> in the "to:" or "cc:" field will bypass my spam filter.
> With most programs "Reply" should do the job.

anon

excellent information christoph, thanks a million for your reply, it
certainly explains a lot.
very much appreciated.
regards.
steve.

"Christoph Bollig" <laserpower@gmx.net> wrote in message
news:q0nqu0lomurj0i26hv2e3d1jp4kc677qbe@4ax.com...
> Hi steve,
>
> > car: audi 80 2.0ltr 16v 1991
> > can anyone tell me what it means when the oil light comes on and beeps
at
> > the same time, i have tried shorting the oil pressure switches to earth
> > which activates the oil light, but no beep, there is plenty of oil in
the
> > engine so i'm figguring it cant be a low level warning lamp.
> > it tends to come on and beep at about 2500 rpm.
> > any advice welcome.
>
> In brief: get the pressure checked as soon as possible. I had a
> similar problem and wrecked my engine by not taking it serious.
>
> What happened was the following (from memory, I might confuse the
> switches):
>
> The Audi 100, 1989 I have has two pressure switches, one is closed at
> no pressure and opens at ~0.3 bar , the other one open at no pressure
> and closes at ~1.8 bar. The auto-check system checks both, but at low
> refs only gives a warning when the pressure is below 0.3 bar. It only
> checks the second switch at somewhere around 2800 rpm. It also checks
> the switches when the engine is not running and gives a warning if
> they don't show zero pressure.
>
> On mine, the low-pressure switch had bad contacts, so that it was
> always "open". I think it had around 10 Ohm when "closed", but that
> was enough for the auto-check to regard it as open. It always gave a
> warning when I turned the ignition before I started the engine, but
> since I was used to have the oil lamp on before the engine starts, I
> didn't pay attention (it was already like this when I got the car).
> Therefore, the system never detected a fault on the 0.3bar switch. At
> some stage, I got oil warnings at around 100km/h. When I reduced the
> speed, the warning was gone again. That was basically the 1.8bar
> switch. The problem disappeared again and came back half a year later.
> By the time I got a proper pressure check, it was too late.
>
> In essence:
>
> - If the autocheck system gives you a warning before you start the
> engine, one of the switches might be faulty.
>
> - Put a DMM on the switch to measure resistance. One of the should
> change immediately when you start the engine. The other one should
> change before you reach 2500 rpm, better much lower.
>
> - Replace the switches, if they don't change properly.
>
> - I would say have the pressure check, if in any doubt.
>
> Christoph
>
> --
> Important: Emails sent to me which contain my full name
> in the "to:" or "cc:" field will bypass my spam filter.
> With most programs "Reply" should do the job.

anon

excellent information christoph, thanks a million for your reply, it
certainly explains a lot.
very much appreciated.
regards.
steve.

"Christoph Bollig" <laserpower@gmx.net> wrote in message
news:q0nqu0lomurj0i26hv2e3d1jp4kc677qbe@4ax.com...
> Hi steve,
>
> > car: audi 80 2.0ltr 16v 1991
> > can anyone tell me what it means when the oil light comes on and beeps
at
> > the same time, i have tried shorting the oil pressure switches to earth
> > which activates the oil light, but no beep, there is plenty of oil in
the
> > engine so i'm figguring it cant be a low level warning lamp.
> > it tends to come on and beep at about 2500 rpm.
> > any advice welcome.
>
> In brief: get the pressure checked as soon as possible. I had a
> similar problem and wrecked my engine by not taking it serious.
>
> What happened was the following (from memory, I might confuse the
> switches):
>
> The Audi 100, 1989 I have has two pressure switches, one is closed at
> no pressure and opens at ~0.3 bar , the other one open at no pressure
> and closes at ~1.8 bar. The auto-check system checks both, but at low
> refs only gives a warning when the pressure is below 0.3 bar. It only
> checks the second switch at somewhere around 2800 rpm. It also checks
> the switches when the engine is not running and gives a warning if
> they don't show zero pressure.
>
> On mine, the low-pressure switch had bad contacts, so that it was
> always "open". I think it had around 10 Ohm when "closed", but that
> was enough for the auto-check to regard it as open. It always gave a
> warning when I turned the ignition before I started the engine, but
> since I was used to have the oil lamp on before the engine starts, I
> didn't pay attention (it was already like this when I got the car).
> Therefore, the system never detected a fault on the 0.3bar switch. At
> some stage, I got oil warnings at around 100km/h. When I reduced the
> speed, the warning was gone again. That was basically the 1.8bar
> switch. The problem disappeared again and came back half a year later.
> By the time I got a proper pressure check, it was too late.
>
> In essence:
>
> - If the autocheck system gives you a warning before you start the
> engine, one of the switches might be faulty.
>
> - Put a DMM on the switch to measure resistance. One of the should
> change immediately when you start the engine. The other one should
> change before you reach 2500 rpm, better much lower.
>
> - Replace the switches, if they don't change properly.
>
> - I would say have the pressure check, if in any doubt.
>
> Christoph
>
> --
> Important: Emails sent to me which contain my full name
> in the "to:" or "cc:" field will bypass my spam filter.
> With most programs "Reply" should do the job.