dead spot on a4 2.5tdi

[quattrov6tdi]

hi all,

a while since my last post.but im back again (coz i have a problem)

Hopefully some one can shed some light for me.

when driving along my a4 seems to get a slight hesitation at about 1800/2000 rpm,maybe a second or so. changed fuel filter and air flow meter ,no difference.(is doesnt happen all the time but it gets more frequent now)

no vagcom faults showing up.audi cant find anything wrong ,but still charged me 700 euros to change faulty injector.

thanks in advance
c

 

[ScottyP45]

only suggestions, but i'd check boost pipes / vacuum leak, n75 or bosch dv if you have these, wastgate sticking open, bad DBW signal from the pedal, the ecu cant see a lot of faults like air leaks and often misses vacuum / boost faults but most things with a sensor should trigger an engine light like the n75 or DBW pedal signal.

Also check o2 sensor for bad fuelling or AF ratio errors which can cause flat spots, if you could get it run on a rolling road dyno with a/f, boost/vac and timing measuring on and you might see whats happening...