fat controller
12-06-2015, 11:26 PM
My internal, paranoid owner is coming to the surface once more......
OK, the plan to upgrade to an A6 is on hold for 6 to 8 months minimum due to some unanticipated expenditure, so the A4 has a stay of execution. The slippy, juddery clutch continues to be a bit of a pain, particularly so on damp/wet/humid days or at the extremes of temperature. Hearing another, similar age A4 Avant TDI in Sainsburys a couple of weeks ago made me realise that mine is barely at the top of the iceberg, as the other blokes one sounded like a bag of spanners in a washing machine - - even a numpty like me could diagnose a knackered DMF from 100 yards.
Anyway, I digress. For the past three or four days, I have had a new issue arrive. It is not always present, and seems to only happen once the car is up to full operating temperature. Essentially, it drives fine - no lack of grunt, no lights, just normal; however, when I pull up at traffic lights and it is in one of its moods, there is a shuddering through the body of the car. After the first couple of times, I twigged that the revs were dropping ever so slightly; for the more mature amongst us, it feels almost exactly like a vacuum leak on an old petrol engine - the revs drop to just under the 800rpm which is what causes the shudder.
It makes no odds if the clutch is up or down (I disabled the auto stop/start to test my theory), and it also makes no odds if the climate control or electrical consumers are on or off.
Now, the thing that is really confusing me is that this is not happening all the time - it comes and goes; when it comes, giving the car a bit of an Italian tune-up seems to relieve things a bit, but then so does parking it up and letting it cool for a while.
Temperature gauge is rock solid in the centre; oil level reads fine; fans seem to work (although it is a rare occasion that I ever notice that they are on) - fuel filter has done about 6000 miles (genuine filter, I believe made by Mann), and all other filters were done at the same time - again, all genuine filters.
I am perplexed. I will endeavour to get a code read done, but I am not expecting to see anything as the car seems otherwise normal - it is only when I stop in traffic or at a junction that I get the problem, and even then it is not all the time - -it does seem to start and then continue for a while before settling down again, if that makes any difference?
Could it be some sort of fuel evaporation?
OK, the plan to upgrade to an A6 is on hold for 6 to 8 months minimum due to some unanticipated expenditure, so the A4 has a stay of execution. The slippy, juddery clutch continues to be a bit of a pain, particularly so on damp/wet/humid days or at the extremes of temperature. Hearing another, similar age A4 Avant TDI in Sainsburys a couple of weeks ago made me realise that mine is barely at the top of the iceberg, as the other blokes one sounded like a bag of spanners in a washing machine - - even a numpty like me could diagnose a knackered DMF from 100 yards.
Anyway, I digress. For the past three or four days, I have had a new issue arrive. It is not always present, and seems to only happen once the car is up to full operating temperature. Essentially, it drives fine - no lack of grunt, no lights, just normal; however, when I pull up at traffic lights and it is in one of its moods, there is a shuddering through the body of the car. After the first couple of times, I twigged that the revs were dropping ever so slightly; for the more mature amongst us, it feels almost exactly like a vacuum leak on an old petrol engine - the revs drop to just under the 800rpm which is what causes the shudder.
It makes no odds if the clutch is up or down (I disabled the auto stop/start to test my theory), and it also makes no odds if the climate control or electrical consumers are on or off.
Now, the thing that is really confusing me is that this is not happening all the time - it comes and goes; when it comes, giving the car a bit of an Italian tune-up seems to relieve things a bit, but then so does parking it up and letting it cool for a while.
Temperature gauge is rock solid in the centre; oil level reads fine; fans seem to work (although it is a rare occasion that I ever notice that they are on) - fuel filter has done about 6000 miles (genuine filter, I believe made by Mann), and all other filters were done at the same time - again, all genuine filters.
I am perplexed. I will endeavour to get a code read done, but I am not expecting to see anything as the car seems otherwise normal - it is only when I stop in traffic or at a junction that I get the problem, and even then it is not all the time - -it does seem to start and then continue for a while before settling down again, if that makes any difference?
Could it be some sort of fuel evaporation?