running like a dog

[accy]

Hi
For the last few weeks (audi a4 1.9tdi 130 avf) the car starts hunting at idle for a few seconds before it settles down at 850 rpm.
The engine sounds loud and very low in power, if i put my foot down say in 2nd gear i get no power until i let go of the acceleration pedal and then reapply again.
No fault codes

Things i have done

Maf replaced with original
smoke test
terraclean
egr replaced
air filter

any help appreciated

[belleekbeetle]

Maybe the injector loom - simple enough job

[accy]

thanks for the response
Wouldn't faulty injector loom show up a code?

[belleekbeetle]

thanks for the response
Wouldn't faulty injector loom show up a code?

Not too sure as I don't have a fault code reader but I recently replaced this loom on a Seat Alhambra TDI PD which was showing these symptoms and it sorted it completely - if you are going to do this job just buy a new loom from any VAG dealer - it is a common fault so they would have it in stock and they are as cheap as anywhere else for a new one - just over £50 incl VAT

[pauldazzle]

If you are using a generic code reader beware as there are a lot of VAG codes they don't recognise. If you do have VCDS look in engine measuring blocks (IIRC block 3) for the temp the ECU is getting from the coolant temp sensor. If it's incorrect the ECU won't fuel correctly & cause all sorts of running issues.