I've got an HKS EVC-IV controller on my STi-3 Wagon and have recently started suffering from boost spiking with it. It will hold boost fine if you allow the boost to build slowly, but if you punch it at high rpm, it spikes - set at 0.8bar it spikes to 1.3!

My initial guess is that the solenoid may be dirty - is there a way to clean it? Alternatively, has anyone got any ideas of what else could be causing it?

Thanks in advance...

mines doing the very same.......and its looking costly, low compresion in one of my chambers..re build time, hope ours is just a simple clean


all the best


jay

Jay

If I turn the boost controller off then I don't seem to get the spiking ...I'll double check later today. The engine only has about 5 thousand miles on it since a rebuild, so I really hope I don't have to go doen that route.

Anyone any ideas for cleaning the solenoids??

Cheers...

same with mine, its still there slightly but no where near as noticable...how much did your rebuild cost you if you dont mind me asking?


jay

If it doesn't spike when AVC-R is off then it is a set up issue. There must be enough air getting to the wastegate actuator to open it when in the off position. The AVC-R just controls this signal, assuming the solenoid is clicking when 'on' and the throttle blipped

Jay - the engine was rebuilt 400 miles before I bought the car - I've got the receipts at home if you want me to dig them out...

Andy.F - I've got an HKS unit not Apexi and it has worked fine until recently, hence thinking that the solenoid could be gunked up, rather than there being a problem with the setup....

Anybody got any answers for this please??

do you have the units scramble setting on?

Willgill - Nope. I've tried resetting the whole thing and getting it to relearn the wastegate, but still get the same problem....