Ok, a lad I know is having problems with his Impreza, it's fine in 1st 2nd & 3rd gear, peaking at 12psi, but in 4th & 5th it's all over the place, the boost is jumping around between 10-20+psi and he's getting fuel cut...

The car is basically a standard UK Impreza Turbo 2000 model, bar a backbox, dump valve and boost gauge (fitted recently to see what's happening), it's a V-Reg '00 car, ~70k miles.

Now it's not just a case of the overboost sensor cutting in early, like I've read about in the SIDC FAQ, it's actually making way too much boost, so there's a problem somewhere.


Anyone seen this before?

 

If the boost solenoid and pipework havent been cleaned then I'd start there. I occasionally get overboost when my solenoid is contaminated although it happens in all gears.

 

I didnt know you frequented here rich

 

You know me mate... I'm a forum *****...

 

Cheers, will get him to clean it up...