sanadrustom

I know its hard to diagnose a car from someone typing, but here is what I have noticed the past couple of weeks:

a rattle that occurs from RPM range of 1500-3500 as you accelerate, its noticeable with all gears. its driving me nuts cause I'm'm thinking its tranny related (almost like the tranny is shaking). its a very noticeable rattle and does come with a bit of shake. I'm not 100% on what it may be and I don't really want to be throwing parts into it if they aren't going to fix the issue.

I will be jacking the car up over the weekend and checking on tranny and engine mounts, but was hoping if someone can tell me what and where I should look for if I am on the right track, or maybe I'm completely off track and someone can straighten me out!

any ideas anyone? help me

Thank you

conall

Pressure plate?
Mine went out rather suddenly, though.

sanadrustom

An update

I was parked at the gas station and when I was leaving I heard a metal on metal sound from when I pressed the clutch in. I pumped it to hear the sound and it's clearly coming from transmission. Is that the pressure plate making the sound? Is it normal or is there play and that's what's rattling on acceleration? I'm starting to think it will need a clutch job soon

Thanks

UrS4boy

Probably the throw-out (aka "release") bearing (Item 15 below). Can only be replaced by removing the transmission. If you remove the transmission, you might as well replace the clutch and maybe the rear crank seal. And oh, by the way, when you have the dual mass flywheel off to do the crank seal, you might as well get it resurfaced (not as easy as with a single mass flywheel). And the flywheel bolts are stretch bolts so they need to be replaced. And with the transmission off, you might as well replace the slave cylinder.

What noises do you hear now?

sanadrustom

This looks like it's going to get pricey. Know of a place where I can price out all those parts or do I have to search around different sites?

sanadrustom

Not sure if this is gonna help but it seems the rattle happens on 2nd great under load :S

UrS4boy

Have you looked at the heat shields around the "Y" downpipe?

The OE "Y" pipe has metal shielding that was intended to keep the heat in the exhaust pipe and therefore warm up the catalytic converters faster. With time, they tended to rust off, partially or fully. Partially, they tend to rattle at various times.

Here is a downpipe with almost all of the heat shield gone, just a little bit left on the right "leg".

sanadrustom

It doesn't sound life heat shield rattle but incase I'm wrong I'll have a look at it and update on that

Thanks Dave

sanadrustom

In respect to the rattle sound. .. out of sheer curiosity I was at a light and I pressed the dif lock button, when the lights turned green I pushed it from 1000 to 3500 rpms and the rattle was loud and well heard does this confirm or clear up if it's a dif related rattle?

sciroccosven

Differentials don't go bad on the audi's unless your power is exceeding the shear strength of the internal parts.. From your other post you seemed to have concern over the rear diff. They are mechanical gear sets that don't have a lot to really go bad unless you have zero fluid. Even then they can still hold up for a very long time.

If your locking the differential your essentially having a higher level of parasitic drivetrain loss require more effort and energyto move the car. It could just be extra strain causing extra vibration. You have the right idea. Start simple, check mounts, all of them and make sure everything is tight and go from there