I have an Audi A4 2001 pd 130, and it has the worst problem you can have with a car! A fault that cannot be found! I have taken it to an audi dealer twice to be told there is no fault! I have taken it to 2 individual diesel specialists who can't find the fault!
1.When under load i.e 2nd/3rd gear using torque to pull away it hesitates... in that the turbo is not present for about 1 second and then spools up (violently if you have planted your right foot)
2. When you turn the engine off the car shakes. This is as if the timing is out, like the engine cylinders are not stopping in correct time.
3. It randomly may work perfectly for a whole week without problem, this is what is really annoying, because you enjoy how the car should be, but then when you need it the most it is dangerous to drive.
4. Large amounts of black smoke pour out of the exhaust when it is playing up. Its as if you put your foot to the floor to make sure you get away on a roundabout and it leaves the car behind a thick black smoke.
Now from every garage that has seen the car they say: we can't find any faults on diagnostics, no errors at all. I have asked all to road test but the car seems to be working fine for them at that time! I have had them change numerous fuel filters and the maf sensor to no avail. It feels like it must be a fuelling issue, yet i don't know if its electrical or mechanical and what it is?
This must be a common fault on the PD130 or either I have the rarest fault ever or perhaps my local audi engineers are just useless at real engineering.
I would really appreciate any help anyone can muster as I have had enough, I have had the car for 3 yrs and it has been great but this fault has been on and off getting worse for the last 2yrs.
Any help appreciated