Hi guys,

My car(06 WRX STI) had been hesitating under acceleration, and not running full boost (O.5BAR). The guys in the garage put an additive to clear out the fuel system, and cleared the boost pipes which they said had a little bit of oil in them. After I took the car out of the garage on Wed it still had the hesitation, but since Sat the car had been running really quick, and smooth again(no hesitations)
This afternoon though the dreaded hesiation when accelerating is back! Any help for this newbie would be much appreciated.

Cheers,

Rick

 

have you got a dump valve on it?

 

Got any air intake modifications?

I'de installed an injen cold air intake system which made this exact problem. I took it off, and it vanished...

 

thanks for the replies.....no the car is totally standard.Cheers

 

What about the check engine warning, is it off?

It can be from the MAF sensor... I'd replace it and check.

 

Sorry...yeah I had the car on all the engine diagnostics in the garage as well. They were all fine, no warning codes at all. Cheers

 

Any other ideas guys? The hesitation has now gone, but there doesnt seem to be the kick in of power now. Nothing like it had been running these last few days after I had got it out of the garage.
Cheers

 

There are no error codes on any of the engine diagnostics, what else could it be?

 

wastegate?

 

Would it be worth trying some BG44K Fuel Cleaner? Worth a go don't you think if the diagnostics isnt showing anything up?
Cheers