Screech/squealing noise when staring car.. changed everything

[Mailbox14]

Hello all,

I need some help from you experts. 2005 Audi A4 B6 1,8T 220,000 KM 6 speed standard.

When I start my car or when I change gears and don't give it enough gas, I get this screeching noise from the engine. Mechanic changed time belt (kit), well because I was over due not because of this noise, as well as the belt to which he thought was the reason for the noise. However, these did not fix the issue.

Any other places to check as I am at a loss and so is here.

On a separate note, the exhaust I had installed (mototec) still vibrates/is touching something, so much that I think it is hitting the back of bumper where the tips are seated. My mechanic told me it looks like the muffler on these exhaust are essentially too big for my car and when he tries to adjust it the other side hangs too low and vise versa.

I took it to an exhaust place and they say all is well because they say the exhaust isn't touching any part of the car and is hanging well. Any better idea on perhaps how to center the mufflers on this exhaust so that the tips are not coming close to touching the bumper (as I think that is my problem) and how to tighten it perhaps a bit better.

Please let me know if you need anymore info.

Thanks again

[Furly]

Did they change the fan belt / serpentine belt ?

[Mailbox14]

Did they change the fan belt / serpentine belt ?

Yes they did.... He also tried spraying some lubricant as I keep complaining and that doesn't do the trick.

Any other ideas?

[old guy]

Did the water pump get replaced along with the timing belt?

[Mailbox14]

Did the water pump get replaced along with the timing belt?

Yes it did old guy....

[old guy]

Yes it did old guy....

OK. The reason I asked is because I had a Geba water pump failure that started making a screeching sound at low RPM. The bearings were shot after 50K miles.

Another possibility could be the idler pulley. I replaced mine around 180k since the bearings were getting loose. It wasn't noisy but it was definitely wobbling.

[Mailbox14]

OK. The reason I asked is because I had a Geba water pump failure that started making a screeching sound at low RPM. The bearings were shot after 50K miles.

Another possibility could be the idler pulley. I replaced mine around 180k since the bearings were getting loose. It wasn't noisy but it was definitely wobbling.

With the timing belt, the idler pulley was changed as well. I suggested that but my mechanic said no. All parts were genuine audi that I put on:( Man if one of the parts were faulty that would be a huge job to redo and I will be peed. Not sure how to proceed here because I am sure my mechanic doesn't want to start taking things apart considering the time and effort.

[old guy]

Just to be clear this is the idler pulley to which I am referring. The idler pulley on the serpentine belt.

[Mailbox14]

Just to be clear this is the idler pulley to which I am referring. The idler pulley on the serpentine belt.

My bad then. This was not changed old guy. I will suggest this to my mechanic. Is there not a quick way to test this (silicone spray) because this may have been what he sprayed and perhaps on this pulley but I didn"t see/hear any result. Noise was still there.

Thanks again.

Thanks again.

[old guy]

He can probably just reach down and try to wiggle the pulley. If it has any wobble at all it should be replaced.

[diagnosticator]

The subject idler pulley must be unloaded to check for bearing wobble. The belt tensioner pulley could be involved in alternative.

[Mailbox14]

Thanks so much to both of you and old guy for the diagram. I will show my mechanic and see what he says. Hopefully that resolves the issue and doesn't cost me a fortune.

May I ask, and hopefully I have reached the limit on my questions:) but any ideas with my exhaust question?

Is there anyway to ensure the exhaust, when vibrating/car running, is not touching any part of car? I find when changing gears that I feel a lot of play in the from and back of the exhaust and think I hear it connecting with something on the car causing the noise. I think it is my mufflers tips that are just touching the back bumper. My mechanic told me he will try to add clamps/spacers next time to left side of the connection but does anyone have an experience with hard to adjust performance exhaust systems specifically mototech's? He says some play is necessary obliviously and that it is tight enough however, I feel otherwise when changing gears.

[MacFady]

I would almost certainly re-iterate what was stated above, just replace the tensioner (serpentine belt tensioner as pictured above) and the idler pulley is also easy to do at the same time. Takes literally 10 minutes for both. Just have a look at the tensioner arm (only other pulley not in blue above) when the car is idling, is there a lot of bouncing/movement back and forth?

[diagnosticator]

With the exhaust system fully warmed up, and the car on a lift, with the engine running at idle speed, visually inspect the exhaust. Any points that are touching need to be marked. Anyplace the exhaust is to close to the body or suspension will touch when the engine moves on the mounts, so a minimum clearance must exist at the places with the least clearance. There will be shiny marks on the exhaust pipes where the pipe touches only when driving the car. After the engine is turned OFF, and the exhaust pipes cooled down, adjust the length and rotational position of the exhaust system for increased clearance in the locations marked. There must be enough clearance for the engine and exhaust to move around without touching anywhere while driving.

[old guy]

The subject idler pulley must be unloaded to check for bearing wobble. The belt tensioner pulley could be involved in alternative.

Here's how you can unload the the tension on the pulley. with the tension off check all of the pulleys for any sign of wobble. If any of them are loose they should be replaced.

[old guy]

With aftermarket exhaust there is always the possibility that the exhaust itself is under a bit of a bind. I had that exact issue about 10 years ago when I installed my Borla exhaust. I ended up having to bend the "Y" section where it attaches to the downpipe to correct the problem. Here are a few old threads that can give you an idea of things to look for: Clicky click 1® and Clicky click 2®

[diagnosticator]

With aftermarket exhaust there is always the possibility that the exhaust itself is under a bit of a bind. I had that exact issue about 10 years ago when I installed my Borla exhaust. I ended up having to bend the "Y" section where it attaches to the downpipe to correct the problem. Here are a few old threads that can give you an idea of things to look for: Clicky click 1® and Clicky click 2®

The value of a good reference data base should not be taken for granted. Thanks for adding the information here!

[Mailbox14]

You guys are unbelievably awesome. I really appreciate the time you all take to write back. Thanks you so much and now me off to the mechanics:)

Have a great weekend all!!