silverA8L

I was driving the family's 00' A8L and noticed the car is significantly noisier than usual. The noise sounds exactly like what I hear when the A/C is on during the summer. Since we live in Toronto, and the temperature is close to 0 degrees C and I have tried to turn the A/C on and off twice to see if it's the A/C noise, which it turned out isn't, can anyone suggest what this noise can come from?

Also, it seems that the car's water temperature is running a lot higher than usual, when I was driving on the highway at 100km/h, the temperature gauge went all the way up to 120 degree C. I normally observe that the temperature is around 95 to 100 degrees C, but it seems that the temperature is running too high. Can anyone confirm this?

Also, do anyone think if these two issues are inter-related? My father didn't notice it until he got out of the car, and he said it could be a bad water pump, the car has about 41000km on it, which we bought new in 00' August (I persuaded him to get it). I'm getting to the point that I'm really disappointed with Audi since our Mercedes didn't have as many isloated problems as the Audi has. We've had the rotors and pads replaced at least 3 times and had leaks along the gas line several times which engaged the check engine light. I love the way the A8L drives and rides and the dealer's service has been excellent, but these little problems are getting to the point that it's irritating. I have a feeling that when we replace the car possibily in the summer this year, we won't be getting the new A8, but rather a 4-matic S500...

icos6

because in my opinion the A8 is much better car.
If You buy s500 please post us about problems You have on it, and please be honest

PaulW

We had a big discussion on the cooling fans (electric and mechanical) and what else might it could be.

It ended up that it was the thermostat.

Not saying that it's your problem, but this was found on a 2000 A8.

When the AC is on in my car, it really doesn't make any more noise, unless it's because the electric fan is running in HIGH speed (is that what you are talking about)?

If your car is noisy because the electric fan is in HIGH and it's not cooling the car, a thermostat could defintely be the culptrit.

pw

TraderAlex

Yes, the MB has too many "active" systems, just waiting to fail. Many of these cars are now reaching point at which "more" is definitely not
"better".

silverA8L

We've narrowed down where that noise comes from. When the car warms up and the water temperature reaches 110 degrees C, the noise kicks in, which I believe is actually what PaulW said, the fan is set on high to try to get as much heat out as possible (explains why it sounds just like the A/C was turned on).

Going to have to make an appointment for service (thank god it's still under warrenty!). We've actually took the car in for little things more often than the actual oil change, which suprises me a lot.

Actually we have a 00' S500 as well and it has been trouble free (but it's not driven as often as the A8). It's a base car with little options. The only problem we've had is the sunroof switch, which just required resycronization. However, the inteior of the 00' S500 just can't compare with the A8, the A8's interior way better.

PaulW

Odd that the thermostat fails and the engine overheats, but that has been a problem before, I bet it might be your problem too.

If you can get the old thermostat, tell the dealer you'd like to keep it. I would like to see it, will post pictures if you don't have a camera.

pw

silverA8L

I'll see what I can do and defintiely report back.

barryl

Hello,

It's fairly easy to determine if the water pump is working,
and if the thermostat is working.

Do you have heat in the car? If the heater works, the water
pump is working. The water pump will pump hot water through
the heater core. So, if you have heat, the water pump is
working. It may be leaking, or otherwise making noise, but
it is working.

For the thermostat test, run the car until the temp gauge reaches
normal operating temp. Turn on the heater and verify that you
have hot air. Now feel one or two of the water hoses that connect
to the radiator. If the hoses are hot, and you can feel water
flowing through them, the thermostat is open and allowing
coolant to flow through the radiator. If the hoses are cool / cold,
the thermostat is bad. It's stuck closed and is not allowing
coolant to flow through the rad. This will eventually lead to
overheating, even on a cold day.

Good luck,
Barry

silverA8L

...to the max, and my father has to stop and let it cool down. He drove the car home and told me about it after I got home. So I called the dealership to reschedule the appointment (it was for next Tuesday). Called the dealer, was advised to call the A8 roadside assistances (in case overheating causes cracked cylinder), which I did, and got an ETA of 3 hours to pick up the car! It was 4:30 when I called, ETA 7:30 for the pick up. An hour to the dealer and I'm afraid the dealer will be closed when I get there and could not get a courtesy car.

I'll keep you all posted as to what causes the problem.

PaulW

out why it failed. You can send it to me and I'll take pictures.

Paul