tarpeyphoto

I've got a 1998.5 A4 1.8T Quattro, that I've had for about 5 years now. I bought it from it's original owner with about 75,xxx on the odometer. It's got 182,xxx miles on it now.

About 6 months ago i started noticing a weird noise that sounds like it is coming from the passenger side of the motor. It happens when I let off of the gas in the lower gears. It might happen in the higher gears too, just not as noticeable. It's a whirrrrrrrrrrrrrrrr noise. It doesn't make the noise while hitting the gas, or while idling.

I've searched the forums and have not been able to find a definite answer. Found quite a few similar posts, but none that were really answered. Some said it was the catalytic converter, some said cam chain tensioner?

Also on a separate note, my motor has become noisy in general lately. Sometimes it's pinging, and constantly kind of a lug lug lug lug lug sound. Is this something that could be fixed by adjusting valves? Could this be the cam chain tensioner?

I know she's probably just getting old and about to blow up or something, so I'm trying to figure out if it's worth the money and what to do.

Help if you can?! Any advice appreciated. Thanks in advance guys.

Howard

Reggie

When was the timing belt last done?

tarpeyphoto

About 30k ago.

turbo510

I had a noise that you could describe that way, turned out to be the wastegate linkage vibrating because of wear. Unless you have extra large hands, you can reach from behind the turbo (engine cold!) and touch the wastegate lever. If you can move it, that probably is a source of noise. The turbo has to come out to readjust the linkage, but you may find that the wastegate disc is also bad.

4Driver4

30k ago what?

xsrfsno225x

...when he had the TB done last

xsrfsno225x

Diverter valve? that kind of whirrR??

tarpeyphoto

Would that be near the Catalytic converter? It definitely sounds like it's coming from that area. But with all noise bouncing around, I guess it's hard to tell.

tarpeyphoto

Its kind of metallic/pingy, I don't know what to really compare it to.

tarpeyphoto

While the "whirring/pinging/crazy" noise that sounds like its coming from the catalytic converter is far more annoying, I feel like the noise that is actually coming from the motor is probably more important to take care of.

I could be wrong about that.

But what would cause the motor to sound that way? Almost like a diesel motor or something. I've always stayed on top of oil changes, and always put premium gas in it. Just to get those questions out of the way. I know it's going to need some work, but I just don't want to play the guessing game and start replacing things that aren't going to fix the problem.

Thanks again.