marcika

Hi!

I have an another problem and a question.
The car is still the 2004 D3 with the 4.2 petrol/benzin engine.
The problem is; After I start the car, sometimes (it happened 3 times) the big warning message for the high coolant temperature suddenly comes to the small board screen (with the 3 beeps). The big air ventilator also turns on - it has a sound like a jet engine - and the message keeps blinking on the screen.
The air temperature was about 18-20 celsius, the car was absolutely cold, and the engine had been running only for 20-25 secs when it happened. I checked the coolant level, it is perfect. Halfway between the min and the max, and it is crystal clear. I let the engine running, and the flow of the coolant looked fine, the pipes started to warm up and also the coolant tank. When the engine get to be around 60 celsius (according the gauge on the board), the warning message just vanished. I drove the car for 30 minutes, everything was fine.
There wasn't any coolant smell nor leaking.

So, I guess there wasn't any real overheating in the engine, but the sensors sent false data to the board. Or if you think there was, I'm ready to listen, I don't want to use the car with these conditions.

Does anybody know where are the thermal sensors for the coolant on this engine? And how many are on the engine? Is it worth to check the memory for errors? Any help are really welcomed!

Thanks in advance!

MP4.2+6.0

Audi's have been kind of notorious for simple coolant sensor issues back to at least the C3 (Audi 5000)/D1 (V8), no matter how much they rev. the part. But, they are pretty inexpensive. Basically its back in the rear area of the "V" fairly low down. Look at part "9" in this link: http://www.jimellisaudiparts.com/sho...roduct=5561097

Mister Bally or others who I think have changed them on the D3 V8 can chime in w/ further specifics.

JohnnyJ A6Q

Hello, I had the same problem on my 2004 A8L D3 4.2, and it was not the G62 coolant sensor, but the coolant level sensor in the coolant reservoir, to which you just replace the whole tank, very simple.

marcika

Thanks for the help!

Hm, it seems it is a really cheap part. Interesting.
When I had to replace to coolant reservoir in my Mazda RX8 it was more than 350 USD...

Mister Bally

As MP 4.2+6.0 says, it's down there, deep down. I thought the Bentley manual was wrong but once I moved some of the tubing around, there it was. Buy an extra retaining clip as it is easy to drop it into no-man's land.

Using diagnostic software should tell you if the coolant temp sensor vs. the coolant level sensor is the problem.

IIRC if the coolant level sensor sends a low coolant signal, the fans do not come on at jumbo jet speed.

marcika

I got the big red warning message, which said the temperature of the coolant is too high. Is there a specified message for the low level of the coolant?

JohnnyJ A6Q

So is the gauge working ? is it stuck on cold ? usually when the the G62 sensor is faulty the gauge hangs on C.
the pic below shows the symbols...

marcika

I got the one of the second column in the second row, which says low coolant level. Hmm. I've always thought it means too hot coolant.

The gauge is working, and it was working through this problem also.
But there is something with the gauge also.
Sometimes when I restart the engine and I know the engine is completely warm, the gauge goes slowly till the middle (90C), sometimes it goes instantly there when I turn the ignition on. (I think the second one is the normal)
Could this problem related to the warning message?

wug

I got error on G62 temperature sensor. I cleared off with VCDS but it keeps on coming after 2-3 days. As for procedure to replace the sensor ElsaWin says to remove the engine. Any advise to replace it without removing the engine?

Many thanks!

carterleeds

hi guys, just a quick input.

with the big coolant light flashing in the middle it is of 2 things. 1. coolant level sensor in the bottle or 2. the G62 sensor which is in the back of the engine.

i hooked up VCDS and it told me G62 coolant temperature sensor which is on the back of the engine.

personally MARCIKA i would put my money on the G62 sensor, because when it goes wrong what ahppens it sends a false signal making the fans go on 24/7 at warp speed lol people thought my car sounded good but little did they know it was a fault. i was not loosing any coolant nor was the tempreture iffy everything was a ok just the big flashing coolant light.

the G62 temp sensor was about £12 here in the uk.

also to get to it its a pain in the *** but try and remove everything you can from the back. if you need pics let me know.

also it has a retainig C clip which is soooooo unbelievably shyteeee its made out of plastic, and i broke like 2 with my big fingers so i suggest you get like 5 of them and tie a tiny string to it. the clips are like £0.35 each so yeh worth it.