Hi I have a boost issue any info would be so much appreciated.
Car is a 1996 wrx v2 import.
Here goes the car would normally boost to 10 psi on the boost guage.but the last week its been hitting 5 psi and holding back.the car has a full blitz nur specR exhaust.k&n induction kit.and a forge blow off valve fitted and ran on Vpower fuel.
I had a split 90° turbo intake pipe so replaced that told it could be that with the split.just replaced it on Monday and put a secondhand maf on.the maf when unplugged stalls the car so think the Maf is OK as my old one done the same.I have had a look at the pipe work it all seems fine no leaks from what I can see.the car has stared to stall when stopping at lights and junctions when its been on boost it would drop to 300rpm then jump back up to 900rpm ish thats if it didnt stall.but when driving with no boost it seems fine.I have checked the codes and got maf and pressure sensor I changed the full 3 port boost solenoid and pressure sensor basically the whole lot of a secondhand car.
I just don't know were to start done some searching and see it could be coils.plugs.leaking boost pipe.the car used to do it a few month ago but only once or twice a week but now its all the time.I have rest the ecu overnight after changing the Maf and bcs.and it was boosting back at 10 psi and pulled strong for a full day and then back to 5 psi.it seems to be fine after you reset the ecu.the car pops and bangs a lot and is using loads of fuel.I changed the fuel filter and oil two months ago.the plugs were changed about a year ago next on my list.
Please any help would be so much appreciated as I am stuck on what to do now.
Thank guys.

 

Does your scoob struggle to start from cold? coolant temp sensor faulty perhaps..just changed mine due to mot emmisions failure (not yet been for retest)

 

Thanks for reply.yea it did struggle to start and was told to change the coolant sensor so I did but it was a used one and still does the same thing.when you reset the battery it seems to cleared what ever is making it do it.but after driveing for a bit it holds back again.
Sick now like.think I will pull the coils and plugs out check for cracks and a new set of plugs.
Could it be the dump valve.
Looking for a standard one if anyone has one for sale thank you.