Took the car out for a weekend play and got up into 5th gear and when the car starts to boost it starts juddering and jerking really violently and will not accelerate through it,i have to back off as it feels like the engine is gonna shake itself to death.The car will go right to the redline in first 4 gears but will not boost in 5th gear,tried taking the dump valve off and blanking it..ITS NOT THAT..Thought it could be fuel surge so upped the fuel pressure to 3bar..ITS NOT THAT.This is really worrying and i dont have a clue what could be wrong..ANYONE KNOW WHAT THIS IS

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ALSO..I Fitted one of these recently.. http://cgi.ebay.co.uk/IMPREZA-WRX-ST...item4ced2160e0 ..but for the version 5/6 99/00...could this be sucking in under high boost/load and causing the above symptoms.

 

Bttt

 

What turbo are you runniing?I would think it is to do with the intake pipe,as I have a similar intake pipe with my md321t and it did the same thing in top gear,it is turbo surge as it cannot flow the air through the pipe where it squashes as it goes past the pwr steering pump res.I have relocated the resovoir and it doesnt really do it at all now but I think that a hard inlet pipe would be better.

 

Im running a vf35 mapped to 334bhp by simon(JGM),my oem pipe had a 40mm rip in it near the turbo end so had to replace it.Thought the demon motorsports version looked good quality and better more expensive than others i saw.Thanks for the info about the pwr steering pump,i`ll try relocating it and maybe put a wide strong jubilee clip around the pipe at that point to help against it sqaushing in.

 

That is exactly what I did with the jubilee clip and it does seem to stop it crushing.

 

Well..i`ve put some strong jubilee clips round the weak area near the power steering pump res,took it out for a run and its STILL DOING IT.I seem to be getting what sounds like compressor surge just before it happens(SEEMS VF35 IS PRONE TO THIS),a sort of fizzing noise a bit like a garden sprinkler as it squirts water out only faster.then the judder starts and if i dont lift off the car will just start juddering and banging violently.

 

Coilpack/s and/or HT lead/s (depending on MY) seriously breaking down?

And/or knackered plugs? Maybe a plug has come loose...?

 

CHEERS for the help bud,my car is a my99 uk turbo and the plugs are almost new NGK PFR7B`s,if not loose could they be gapped wrong,what should they be? simon jgm told me but i`ve forgot,i`ll get to checking them first thing tomorrow

 

0.7mm. Or 0.65mm if you want to be "certain" the boost won't blow the spark out.

 

Glen it dont sound like spark blow out you got,come take me out in the car,it sounds like good old vf35 surge,its a bad combination running a vf35 + fmic+ silicone inlet with induction.

 

Nice 1 Pete.. that would be great if your sure you dont mind pal,just let me know when you can spare the time and i`ll come and pick you up.i`ve sent you a pm on sheff scoobys,MUCH APPRECIATED BUD.

 

Did you succeed to solve the issue ? I am asking as it seems I have the exact same thing and getting worried

 

No i have not sorted it as yet mate,waiting until the mapper has a look at the car in a couple of weeks.it sounds like bad surge from the turbo as i have replaced the standard induction/intake hose with an uprated silicon version,and this along with an induction kit and vf35 make for serious surge problems im told.