cblackob

So I searched the forums far and wide and couldn't find anything on this in particular. A few days ago upon a cold winter start up in Maine, I noticed this pulsing, rattle/grinding sound. It went away shortly I popped the good to listen, and it was very quiet but there was almost a ratel or grinding sound coming from the drivers side timing belt cover. I drove to the shop where I had my timing belt done in late November. The mechanic un clipped the timing cover and there were two deep grooves almost right in the middle of the belt. I'm lucky I caught this but pretty frustrated as I have other things to take car of on this car ( b5 a4) . Have any of you guys ever heard of or seen grooves dug into the smooth side of a timing belt? I'm wondering what could have cause this?

cblackob

Bump

Sambar Stag

Yes, cblackob, I have seen such a thing. On my previous B5 with the 12v 2.8l motor I had a groove worn about 1/3 of the way across that wore down to where the belt split partway through in one section. The reason was a failed idler pully; its bearing ***** had come out of the races and were loose down inside the lower timing cover. The pulley became severly misaligned and caused the belt to slip down straining the water pump also. Mind you, this was the car's second belt, with all "OEM" parts with less than 50,000 mi. on them. I hope you have stopped driving the car; get that timing belt and all the parts it runs on replaced NOW if you want to save your engine. You are fortunate and astute enough to notice the rumbling noise before permanent catastrophic damage occurs.

cblackob

So it's been a week about, I took it to the shop that did the tb change and they took it all apart and told me they could find nothing wrong with any components because the parts are covered under the warranty, if something from the kit had failed early, it could be replaced. I've been popping open the timing belt cover everyday since they replaced the belt ( of course it wasn't free 242 just for the labor not bad but not cheap ) and just yesterday I noticed the start of the two same grooves running the whole length of the belt!! I am unemployed because I just got laid off so this is all very stressful especially since the a4 transports me and my kid and gf everywhere! The grooves aren't exactly dug in to the belt yet but you can see two lines. The only thing I can thing is it has to do with the covers. The mechanic said he didn't see anything wrong with the tb components or the covers. I am stumped.