Hi all, This may sound a bit vague, but I was wondering if anyone could give me a few ideas what my problem may be. Over the past 500 kms of driving, my trusty TDi (1.9) Golf, it has decided to derate on occasion. When this occurs, I feel a sudden loss of power and the maximum fuel delivery is around 7.2 litres/100km according to the display, or 2200 rpm. I've changed the fuel filter and inspected the old one for contaminants - all appears to be fine. Once started again, the Golf performs as it should for a while then when putting my foot down (wide open throttle) everything is okay for a while and all of a sudden, the engine derates again. On occasion, I can pull over, shut the engine down, key out, wait a few seconds, re-start and she's fine for a while, then the scenario repeats itself. Never has the 'check engine' light appeared. I thought it might have been the MAF sensor, so borrowed a good one, tried this and all seemed to be working okay until today on my way home from a 400 km round trip. I was going up a steep hill, put my foot down and again the engine derated - max 2200 rpm, with an obvious decrease in power. On this occasion the 'check engine' light illuminated. I limped home (55 kms) not wanting to risk the engine not starting again, as there is no mobile (cell) phone reception where I live. The car didn't let me down, but it was a painful last 55 kms, only having around 1/2 the normal power. Once safely home, I shut the engine down, waited until everything went off (dash display), re-started engine and the 'check engine' light remains illuminated. I've not taken it for a drive again, fearful of causing damage. Sadly I don't have a scanner, so can only guess what the problem may be. The vehicle has only just turned over 90,000 kms and I plan to take it to a VW dealer for the timing belt and water pump in another 10,000 kms, but that entails a 200 km drive in the Golf, or put it on my car trailer and tow it there. Until then, I'm going to try and figure out what this problem may be, or see if anyone I know has a suitable scanner. In the interim, I would love to hear from forum members who may have experienced something similar, so I can look at all possible causes.... (throttle position sensor?). Thanks in advance.