Hi folks. thanks for reading :/
Bought my '56 TDiQ 170 a couple of months back, seemed to be a good enough motor until the last week or two. Couple of times it's lost power while driving, both times it's been wet with lots of standing water on the roads - which I avoid if I can - so I don't know if that's relevant.
A couple of weeks back, 15 minutes into my commute home, really heavy rain on the M25, loads of spray, it started to lose power - just felt like it had dropped a cylinder, and struggled to get past 2000 RPM unless I absolutely floored it, but even then you could tell something wasn't happy.
Today, on the M4, an hour into my commute to work it began to lose power, same symptoms, but this time I could worryingly hear a scraping noise coming from the engine bay - at least that's where it sounded like it was coming from - much like the sound of a brake pad scraping on a disc. Press the clutch, noise goes away, engine revs freely in neutral. Engage a gear, noise is there and increases in volume as you apply engine load with the throttle. Just coming onto the M4 slip from the M25, I thought my exhaust had gone, as it was suddenly really boomy when the revs went from idle to about 1100 - blip the throttle, boom. Really weird :/
I know it's a long shot, and I know I need to get the fault codes read (presuming there are some but does this ring bells with anyone?. There are no warning lights, no increase or decrease in temperature, no whistles or bangs. The only other thing I've noticed is that when parked, if you pull away slowly on full lock, to manoeuvre in a car park etc, there's a juddering/vibration through all 4 wheels - but it's only momentary as you go from being still, to setting off, so I guess it's just the haldex sorting itself out? Again, maybe (hopefully!!) a red herring.
Car had an oil and oil filter change at Audi a month ago, I just fitted a new air filter and fuel filter, which has dramatically improved the responsiveness and MPG (as you would expect). I don't thrash it, but I do put my foot down every so often. Always sit at the speed limit or thereabouts, on motorways with cruise engaged. It's had the injector recall but I don't know whether it was all 4, and/or the loom - will call Audi shortly.
Any thoughts, very welcome...