jordeeeezy

Turning to the forum family for this one.. so I've been having a problem with my 01 A4 Quattro, at least I think it's a problem. What's been happening is that after driving, I shut my car off and when I turn it on after a minute or so, the temperature gauge needle moves up to the first line. I first noticed this while I was driving my car, I noticed that the needle would go smack dab in the middle and it slowly climbed up a little but then would move back down as I started driving. I took it to the mechanic who replaced my timing belt and they replaced the coolant temp sensor and thermostat (again). Now, the needle would sit a tad on the cool side while driving, sometimes it would move directly to the middle but nothing towards the hot side.

Brianna Belstler

I have a 2003 A4 Quattro and this exact thing is happening to me and I have no idea what to do. The place I took it to told me it was a cracked cylinder or blown head gasket as well.Took it into the shop today to see what they say.

eatlas

WELL, if it's the coolant temp gauge, then I've read YES, it should go to the top/middle when you shut your car off after driving a little while, maybe even a bit over to the right. The reason for this being that when you're car is running and driving, coolant is being actively run threw the system, flowing & in motion throughout the various coolant lines, etc... keeping the coolant at reasonably "low" temps, probably around 1/4 of the way on the gauge.

Now, when you shut the car off, the coolant then becomes still. This means the coolant is going to become much hotter because it is no longer in motion, no longer being moved around the engine thus no longer transferring its heat as well.

Think: when riding a bike, you may sweat a bit and breath a bit heavy whilst riding, but if/when you come to a sudden stop... a minute or so later you'll likely start sweating profusely.

So if you when you're driving the gauge is at 1/4 of the way, then when you stop, get out, then turn the car on 5-10 minutes later & the gauge is at 1/2 way + 1 notch maybe, you should be alright. My car does the same thing.

Only if the gauge was like 3/4 of the way would I be concerned.

jordeeeezy

I was told it's normal by many Audi people. As long as it doesn't pass the 5/6 line then you should be good. I did a pressure test myself (rented the compression tool) and was getting equal pressure in each cylinder. Watch a how to on YouTube. So no cracked head and properly sealed gasket. I know the coolant flange goes bad (replaced it on 2 Audi's and a VW) so it could be that. Good luck! Hopefully it isn't too bad.

Thanks for the info. I found that yeah it was normal. As for the bubbling, it was because I had air in my heater core. Heater core wasn't blowing hot too. Finally flushed it, got heat and no bubbling. The guys at Audi were nice enough to tell give me a solution rather than them diagnosing and charging me. The coolant temp has never gone passed middle in other cars so it worried me when it was mine. Didn't know it was normal. Thanks again though

eatlas

Good stuff man