ripnriding

I have a 98 A4 1.8T with 240K on it. Last winter I would start the car up and occasionally it would emmit a strange squeal...kind of like a sickly horn sound. It would disappear in a couple of seconds. Wasn't too concerned as it wasn't frequent.

This sound is now daily and only present when my climate control is on...not present when the climate control is off. My temp gauge also seems to be running low, barely getting up from lowest setting. Any ideas? Timing belt was replaced last year.

a4audi4fun

Squealing likely comes from the AC belt. Trying dabbing a little dishwashing soap on the inside of the belt. Don't use too much - you just want to reduce the belt friction very slightly. My mechanic Dad showed me this trick a long time to stop squealing belts. Used it on many cars since then...

ripnriding

Thanks for the opinion...familiar with Timing belt squeal...not that kind of sound and wouldn't jive with the climate control on/off test. Any other ideas....I'm thinking it has something to do with either the water pump or heating core......

scotta4

your thermostat is toast fix it asap running cold is bad for your car and you are just going to end up causing more wear than is necessary. the 2.8L is easy once you get the front of the car off im sure its the same with the 1.8. I have the same squealing problem with my 2.8L and it has something to do with the air conditioning system when i shut it off after iv turned it on it goes away. its a very odd sound and only lasts about 10 seconds early in the morning so its hard to diagnose.

ripnriding

Scott,

Thanks man.....That sounds like it....I'll get it changed with upcoming oil change

rusty_67

iTrader: (1)

If it only comes on with the climate control on could it possibly have something to do with the ac compressor? Try turning the econ on and off and see if that affects the noise. If it doesn't affect the noise it's more likely that it is the thermostat. My only question about that would be why would the thermostat make any kind of noise.

Oh and the timing belt shouldn't ever squeal as it is a toothed belt. He was suggesting the accessory belt. Did you replace anything else when you did the timing belt?

scotta4

the thermostat is the reason it is running COLD not the noise. As for the squeal i have no idea there is 2 problems here with more than one solution. With the 2.8 the thermostat is behind the timing belt. if its the same as the 1.8 make sure you don't get any coolant on the belt when you are pulling it apart. Like i said if its anything like the 2.8 its impossible to reach while the front of the car is on ... you need to take the entire core support off so its not as easy as changing it while you are doing an oil change.
On a second note go to the dealer for a part like a thermostat: over the years i have had nothing but problems with aftermarket ones they either run too hot or too cold. This kind of thing i have always found is worth the 10 or 20 dollars extra to do it right the first time especially with the amount of work you do on an audi.
If you are going to do it and have the cash laying around if you have it all ripped apart id just pay the money and do the accessory belt and tensioner while you are at it, at the very least the belt because thats the cheapest solution i can think of.

probably the hardest part of doing mine was bleeding the coolant system after. the rad support is really easy to get off once you have pulled off the bumper you just need to make sure you put the ac radiator off to the side and not trip on it. Do not try to avoid this the step of pulling off the core support to save time because it will only take longer i can 100% gaurentee it. It makes working on the car feel enjoyable when you can reach and see everything easy.

rusty_67

iTrader: (1)

Sorry I realize that now.

ripnriding

Thanks guys....always troubleshooting to/from work. Yup, no squeal when AC is turned off and does have a metal AC compressor type sound when on.....The thermostat is recording temps one notch above 60....climate here in Canada is 5-10 degrees...I'll look at owners manual regarding regular temps...car has over 240 k....won't fix AC...will use windows more in summer. Thanks for all the tips guys this forum is gold