hi everyone,
can anyone tell me why my subaru impreza sti back fires at 4000 to 5000rpm.it happens when i put me foot down,im sure this isnt normal.my subaru is @341bhp but lags that power now.is it the blow off valve,intercooler?please help me!thank you

 

I believe this can be caused by turbo lag .

 

this is only started to do it what can i do

 

what can be done to stop this turbo lag?thank you

 

Give the guys a run down of what year/spec your car is that will help them, also are you running a standard dump valve or is it a vent to atmosphere type ?

 

oh sorry its 1994 model jap import standard dump valve,green cotton air filter
full stainless steel exhuast decated,ecu chip its on a blue number engine so ive been told,its number 4 out of 10 special editions made in japan

 

'Blue-printed' do you mean?
Is it a wrx or sti?

 

Welcome to the forum by the way

Sorry I'm no tech head so I'm not able to advise you on this but the more info the better for the guys that are.

What I will ask is have you had the car long and what fuel are you running in it ?

Simon

 

its a sti,ive had it for 12 months now it was import in2004 i run it on tesco ultimate fuel does that help at all thank you

 

what is blue printed anyway?

 

Could be overfuelling.