Over the last month or so i've noticed that i tend to get a kick in power at 5K revs, below this it builds smoothly. The only mods are a panel filter and racebox rear silencer.

Could it be something has finally freed itself or that something is now sticking?

Thanks in advance.

 

Your boost solonoid might need a good cleaning

some brake cleaner should do the trick, a common thing on imprezas

 

Does it have AVCS (VVT-style) heads? Could it be the aggressive cam-profile kicking in? (perhaps they were not working very well before?).

 

Probably just the fact that it is unmapped and it is spiking boost.

 

A stick/faulty Neutral Position Switch makes the AVCS stop operating, so the car feels really smooth if a little gutless, when the NPS starts to work again, the AVCS kicks in and you will feel a surge as the cams alter their timing.

All i.m.h.o.

dunx

 

Don't know about AVCS, I've a standard MY52 wrx.

Cheers all.

 

i had this on my bug had a look and found a split vacum hose! the power was there but not properly as if it was running half boost then it really hit in at around 5k as if the turbo was making full boost then.

 

Just had a look in the workshop manual but cannot fond a boost solenoid, clues as to it's location.

Ta,

 

Sorry !

Just sounded like my "problem" in 2007 !

dunx

 

how can i tell if my x reg wrx jdm has avcs as i feel like i have a twin stage turbo but when the turbo kicks in at 3500 it hesitates? then drive throught it goes well steve

 

To the left of the engine bay mate.
In front of the drivers strut, remove the cover being held in with two plastic screws. Your boost solenoid is blue. Unplug it, then unbolt it and remove vaccum pipes.

Steve