audi s3 boost issue

[Turbo_scotty]

long story short

stage 2 revo ( with sps )
intake
decat
autotech fuel pump
dw65v intank ( just fitted )
new afm

just fitted the intank pump due to getting soft limp 12555 code this is now sorted and code is gone ! but boost feels like its on and off when wot could this be my n75 ? car pulls 260gs via air flow but stuggles to get there and is all over the place its also had a new genuine maf about 4 weeks ago

any idea can do logs or anything required

cheers scott

 

[Turbo_scotty]

just to add also just had new plugs bkr8eix

 

[S3Alex]

First thought would be why you fitted a dw65v pump instead of an OEM replacement which is designed to work with the PWM fuel pump controller on your car.

 

[Turbo_scotty]

I fitted a dw65 as my o.e pump was failing and couldn't find a new replacement and didn't want a used one .

Cheers Scott

 

[S3Alex]

Thing is you've bought and fitted a pump aimed at the 1.8T market which is not best suited to the S3

Most of the good tuners can easily source a new OEM pump.

 

[Turbo_scotty]

I was just goin with what I found every website I went on said it was a replacement so I went with it. Guessing that's goin to be my problem then yeah ? Car runs fine apart from the boosting and it only does it just after you change gear feels like it spikes drops off then spikes again . Cars never run correctly since I bought it so unsure if this is how it's suppost to be .

 

[S3Alex]

You need to have the fuelling and boost logged to find out what's going on now after the pump was fitted.

If it's not flowing enough fuel or the controller is mapped for the original pump then problems may result.

 

[Turbo_scotty]

I have vag com so can log whateva think fuel trims on there are 103 or 106 ? Correct me if I'm wrong ??? I'll do a few pulls later and post results

i only fitted the fuel pump yesterday don't get me wrong car feels 1000% better than it did as it was pritty flat (due to fuel pressure) I'm a mechanic so I do all my work myself built a few 1.8ts still learning the ins and outs of the tfsi .

Cheers Scott

 

[S3Alex]

I have vag com so can log whateva think fuel trims on there are 103 or 106 ? Correct me if I'm wrong ??? I'll do a few pulls later and post results

i only fitted the fuel pump yesterday don't get me wrong car feels 1000% better than it did as it was pritty flat (due to fuel pressure) I'm a mechanic so I do all my work myself built a few 1.8ts still learning the ins and outs of the tfsi .

Cheers Scott

OK...you've got quite a head start on many of us if you can do the work yourself.

The S3 uses a PWM controller for the LP fuel pump,and the Dw pump is not aimed at that engine,more towards the 1.8T market to be honest.

The mapping certainly needs sorting out,but it would be best to have it logged by a Revo dealer to find out exactly what it's all doing,and across the rpm range.