just after some advice.
i have noticed recently that my tail pipe is very black and sooty and the car seems to get sluggish from time to time, unless i get it on vagcom and clear fault codes which i have heard resets fuel trims, then its all good for a while.
i have had a new turbo and cat recently, just wandering maybe as the turbo wasnt working could the engine have not been burning its fuel properly and buggered the lambda maybe??
any suggestions would be great.
surely though, if the lambda was broken that it would show up, it might be the it is not timed correctly and getting a really nasty burn. try using some injector cleaner like redex or millers oils