Maulroad

I'm wrapping up my torque converter project and hit a snag. The car (2004 4.2 allroad) is back in one piece after TC rebuild, main seal, oil pan gasket, tranny filter service, spark plugs, coolant flush, aux radiator replacement, filters, etc. I got a clean read from vagcom except for the p1577 motor mount failure. The car shakes at idle and gets worse in the test drive. We noticed excessive heat coming from around the air intake box. The test drive was also loud (fan/whine noise from engine compartment) and worsens with gas/speed. When we opened up the hood, the entire engine compartment felt too warm, but oil temp read normal.

Thoughts? The p1577 code wasn't there before tearing the car apart. Seems odd that it failed because we removed it.

Maulroad

I did another shakedown drive last night. I reinstalled the air intake plastics and ran the heater (to test the cooling system). I don't know what was wrong before, but the engine bay seems to be a reasonable temp now.

The engine mount code wont go away and the cars still shakes. The vibration is worst when idling. At speed, the shake is less noticeable. The engine sounds good and isn't throwing any other bad codes. The tranny shifts smoothly and power seems to be normal.

Prior to the tear down, I scanned the car with a generic OBD2. The only code it pulled was for the torque converter. Currently, the CEL is off but the VCDS finds the engine mount code. I guess the mounts could have been bad before - but I didn't have the same vibrations. I can't understand how removing and installing the mounts would have damaged them.

I'm tempted to swap the mounts, but $500 and a day of work is a big gamble for a guess.

Maulroad

This isn't a popular thread, but I figured I'd update it just in case it shows up in someones search.

I put in new engine mounts. P1577 code was clear, but the shake was still there. Talked to some mechanics and the consensus was that the torque converter was out of balance. I called Sam (517 Trans) who rebuild the TC and he said, among other things, TC balance wouldn't create a shake that was worse at low RPMs and better at higher RPMs. He thought the crank pulley (harmonic balancer) could be the problem. The rest is a cross-post from Audizine:

I have some updates!!

(1) Sam from 517 nailed it with his over-the-phone diagnostic. I put my crank pulley on wrong (180 degrees off).

(2) 4.2 Allroad crank pulleys should have dowel-sleeves installed on one of the bolt holes. This aligns with a counter-sunk hole in the crankshaft. This is also why Alldata says the pulley will only go on one way.

(3) My sleeve is missing (either due to my own sloppiness or a prior mechanic). I'm certain that it is removable because (a) it's gone and (b) JHM's lightweight pulley installation notes say: "Also note that one bolt hole has a dowel in the stock pulley and must be removed and inserted into the JHM pulley."

(4) Audi does NOT have a part number for the dowel-sleeve for the 4.2 Allroad

(5) Awesome parts guy at the dealer was able to look up ALL alignment sleeves and narrow it down to one possible part (11.125mm x 6.5mm). This is the sleeve used in the R8...so my car will be pretty fast after this mod.

The sad wagon has been in the garage since Thanksgiving. With a little luck, she'll be on the road by Sunday!