Hi guys, im hoping someone may be able to shed some light on a problem im having with my car, as im now running out of ideas! (Apologies in advance for the long post!)

Its a 1996 V2 Impreza WRX Vltd.

Im having intermittant boost problems. Around 80% of the time it runs fine, driving smoothly and making 1.0 bar of boost.

However sometimes it will only run 0.8 bar, sometimes staying there and holding back, other times it will slowly make it back to 1.0 bar but still will seem to stutter like a misfire (knock link doesn't like it either).

So far i have been to Powerstation in Tewksbury to try and diagnose the problem. Thankfully it played up on the dyno. First off they changed all of my vac lines leading to the boost solenoid and checked the restrictor pill. Still had the same problem. Then they swapped over the boost solenoid. This solved the problem. (Or so i thought) Put my standard one back on so i could drive home and it behaved like normal again.

I have since swapped mine for a new one (used but known to be working) and it still plays up!

The car did have a HKS dump valve which i thought may be leaking, since changed it back to a stock one. No change. I have also checked the ECU for codes (none come up) and reset the ecu.

The car has the following modifications...

HKS Downpipe
TSL Group N exhaust system
APEXI intake
HKS front mount
Z4 ECU (ESL V1.0 board)
Walbro fuel pump


If anyone has any ideas or suggestions i would be greatful!

Thanks Adam

 

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