low power 2.5tdi

[Joni_s]

I have an a4 2.5 tdi quattro which has never seemed very fast considering its supposed to be a 150bhp model (AFB engine).

I had it vag com'd by a mate last night and the MAF was reashing a maximum of 550/stroke when the engine really needed aroun 800/stroke according to vag.com.

I've change the MAF twice now and the latest one was a BOSCH so i think thats ok. I also need to change my air filter which should help a bit but are there any other obvious other things i should be checking given that its down on power?

One otehr thing.... the metal link pipe at the front of the car below the bumper which links the two intercoolers together has some rust and possibly a hole in it. This may be causing problems as the compressed air from the turbo could be leaking out before reaching the inlet manifold.

Other than what i've mentioned i.e. MAF, air filter, possible leak on metal pipe are there any other common problems to look for whenexperiencing reduced power (its not limp mode and no faults codes came up on vag.com).

Cheers.

 

[quattrojames]

Certainly on the later AKE engined 2.5's frequent problems are to do with the Fuel Injection pump (doesn't always show a code), or more likely by the sounds of your problem the vanes in the turbo get sooted up.

 

[Joni_s]

James, cheers for this. Is it possible to easily take the turbo to bits and give it a clean up?

As for the fuel injection pump. How can i check if its faulty?

cheers.

 

[quattrojames]

Testing my knowledge here, but ......

1) The turbo can be removed and cleaned with carb cleaner, how "easy" that is I don't know as I have never done it.
2) "I THINK" that the only way to tell is an experienced technician to tell you, or to remove it and send it off for testing and refurbishment. Which I understand is quite expensive.

Sorry to be so vague, let us know how you go.