I have an R-reg VR6 with 85k on the clock, full VW history and oil changes every 6k miles etc. etc. The engine has recently developed a rattle and I can't quite pinpoint where it's coming from. It gets louder when I rev the engine, but seems to fade a bit when the oil temp reaches around 70 deg C. It never really disappears altogether though - I can always hear it in the background. Could it be be worn upper guide rail and/or tensioner or maybe worn hydraulic tappets? If so, are either of these expensive to fix? The car has recently had a full service, with no problems reported. Any ideas/suggestions greatly appreciated. Cheers
if it is them, they are pricey to fix due to the fact that either the engine or the gearbox has to be removed.
Early mileage for the chain/rails to go though, I'd try a change or clean of the tappets first. I've driven a few VR's with over 130k on them that had never seen the dreaded rattle yet, and they weren't exactly driven sympathetically.......
The upper rail on early cars weren't that good, just plastic crap. I think the later upper rail are strengthened, or so i read on vwvortex.