pablo_ottawa

Hi guys,

I have a 2 part symptom that I'd like to get some opinions on.

Last night I went to start my car to warm it up. Outside temp was -18 CELCIUS. The cimate control was set to windshield defrost to heat up the front windshield. This drives the fan up to its max setting even though the engine is nowhere near its idling temp.

The car was on for about 20 mins which is more than enough time for the car to warm up even at -18.

When I finally got into the car I found that the air coming out of the vents was not very hot which is not normal. Also, I noticed that the needle on the temp gauge had only reached the 1/4 mark on the dial as opposed to the middle normal idling temp (90).

Would anyone know what the HELL is going on??? I'm gonna go a vag scan when I get home but in the meantime I'm hoping it's an easy fix....

Anyone?

a4audi4fun

You're saying you idled the car for 20 mins. If it's -18C outside, I'm not surprised that after 20 mins the temp guage was still only at 1/4. When it's 0C here, I still have to drive the car gently (max 3000 rpms) for 6-8 mins to get the temp guage to reach the 90C position. From -18C cold, it's going to take a lot of idling to get any sort of heat into the engine. Also if you have the fan in the defrost position at that point you are actually FORCING -18C air over the interior heating coils; think that would mean you were cooling things down rather than heating things up.

pablo_ottawa

I see what you mean and it does makes sense but from my understanding of things, the thermostat stays closed until the engine reaches idling temp. Once the engine reaches idling temp (needle hits dead middle), the thermostat opens up to allow coolant to the engine.

I`ve read other similar posts and it could be that there is air stuck in the cooling system or heater core which may be the reason as I recently opened the coolant resevoir to put more coolant in the engine.

So in response to your post I'm now wondering if everyone else's B6 takes over 20 mins to reach idling temp when the windshield defrost button is on.

One cheap solution I read about was to just unscrew the coolant res cap and leave it loose then let the car run for 30 mins till it reaches idling temp. Then rev the engine to get all the air out of the cooling system thereby bleeding out all the air.


Has anyone ever tried this?

P.S. you shouldn't have to run the car for more than 30 mins to get it to warm up. It *should* warm up while parked and idling. Technically this should also be possible no matter what setting is on the climate control.

a4rob

your not supposed to let your car warm up while idling. The cars are designed to be turned on and driven to warm up.

Been multiple threads about that in particular.

pablo_ottawa

Well,

I just brought it into Tapp in Ottawa (great bunch of guys) and they did the heater core flush and although the HC wasn't blocked or clogged it was good preventative maintenance. The problem was actually smaller than anticipated.

As I said in a previous post, there were some air pockets that had accumulated and that is why I wasn't getting as much heat as usual. Also, the tech discovered that the "J" plug was leaking coolant (commonly called the J plug because it's a plug that is shaped like a "J"). This may have been the culprit. As coolant leaked it eventually reached a level low enough that the res was starved for coolant. This causes air to be trapped in the coolant lines which results in a blockage. Short term solution is to just keep the coolant topped off until I can bring the car in to have the "J" plug replaced.

@A4ROB,

I don't see why letting a car warm up when it's -28 degrees Celsius outside would be a bad thing. I'll do a search and read the posts but I don't see how gently driving a car and the engine at -28 would be better than letting it warm up.

pablo_ottawa

@A4 Rob....

Found these posts which makes tons of sense. Could not have said it better myself

"Yeah, you're aSoCal boy alright, Chef!
When it's single digits here in the midwest (yesterday morning the car's thermometer said it was -1F), the oil is really thick and doesn't flow too well around an ice cold engine block. I have an old pick-up that stays out in the weather year round. When I start it in the winter, the engine groans until the oil starts to flow.
So, yeah, I let the car warm up several minutes before throwing it down the road. It gives the oil a chance to warm up and become viscous enought to protect all the moving parts."



"It is important to let the engine warm up in general at least for bit, to let the oil get into all of the parts before driving, especially when the oil is cold.Like Sancho said, I usually let it idle until it drops under 1k. Too much idling is just a waste of gas and is actually not good for the car. Warming up is also good fora turbo car. Havingseveral twin turbo RX-7's, it was one the essential rules to both warm it up and to make sure to cool it down, many of the guys would get turbo timers as well."

http://www.audiforums.com/forum/audi...-engine-53886/



Here in Canada, if you're not letting your car warm up at least for 5 mins when it's -28 outside, you're doing more bad than good.

MapleSyrup

I dont think a4rob ment to say your not suppose to let it idle , i atleast let it idle below 1k as stated but that is only about 1min-3mins depending on how cold the weather is, i believe he ment your not suppose to let the car idle for 20mins... for that will not cause the engine temp to rise to 90C and wastes your gas.

pablo_ottawa

I agree..... so now it's just comes down to personal comfort and to be honest, I LOOOOVE a toasty warm car to step into and drive. Now, the more I think about it , the more I'm of the opinion that a good 10 minutes would be WAY better in extremely cold conditions. Think about it! 2 minutes won't do much to loosen up the oil so a 2 minute warm up and then driving would put undue stress on the oil circulation system primarily the sump.

If wasting precious gas is the only consequence of a 10 minute warm-up then I'll take the hit and do a 10 minute warm up. I would rather have the oil nice and loose before even putting it into gear.



From what I've read on both this forum and audiforums.com, It's a very controversial issue but it really seems to come down to personal preference.

maxaudi

Same here.

ken0306

I got the same problem too, the temperatures only read as 50 even you drive for a while. It is mostly looks like the temp sensor and thermostats need to be replace.
I got my fixed by changing sensor and thermostats 2 days ago.