When driving down the motorway earlier today, and getting to 75mph, all power to the engine seemed to dissapear for a split second, almost like a splutter, then come back. It doesn't happen in lower gears just in fifth and at higher speeds??
I have spoken to my mechanic and he seems to think it may be the air flow sensor getting clogged up by the oil comming off the induction kit, as on the impreza's the air filter should be a dry (foam) filter.
Can anybody shed any light on this? Cheers

It's a '99 uk turbo by the way

 

could be overboost causing fuel cut. was it like hitting a brick wall?

 

Sounds like an over boost to me too! Check wastegate through.

 

yes it does feel like hitting a wall!! but only for a split second then power will build up again. I have recently put a bailey dump valve on also, so could that have anything to do with it??

Cheers Mike

 

If it happens when flooring it then I would agree with overboost - same happened to me after my remap. The chappie who mapped it tweaked a couple of things and it's been fine since

Does feel awful though - and makes you look pretty foolish when overtaking someone lol

 

Damn right it makes you feel stupid, especialy when being over taken by one of those gay looking bmw's with no boot