Did a search and found nothing so here is my story

I have a 1987 Audi 5000CD turbo Quattro which has a major hesistation issue at full Throttle. If I accelerate at full throttle the car runs fine up to 3000rpm where it starts to produce boost and then hesistates like crazy and the engine will not go over 4000rpm until I release the pedal to half throttle. At a certain point at half throttle the car will run smooth, rev to redline and produce good boost and drive like a normal car. If I do not go more than half throttle the cars runs perfectly fine, except for a slight high idle. Let's say I am on the highway in 4th 3000rpm doing around 100km/h and then punch it the car will hesistate like crazy and will not increase in RPM until I release the throttle to half and at a certain point the car kicks in and is fast like crazy.

The only engine mods the car has is a chip, bigger 2 piece exhaust manifold and a K&N drop in filter.

Things we have checked

Changed the computer which made no difference
Check the frequency valve, found to be good
Changed fuel distributor and fuel pump relay

This car is my camping, winter car and I love it and it drives great except for this hesistation which I would love to fix as I know she can move more than she does right now.

If anyone can point me in the right direction or give me some ideas that would be great.

Cheers,

Paul

 

check on the throtle position switch