Boost problems...Help!!
 

Hey, I just upgraded from my '91 Na FC, so a beautiful '93 R1. The car is in perfect shape and everything works wonderfully.

The only problem I am having with it is if I ever reach more than around 4800 rpm in any gear my boost drops from 10 to 2 and it wont raise back up until i lay off the gas completely for like 4 seconds. Even if I shift into another gear and give it a go, it will still only boost to 2 psi.

Everything is stock on the car. Up until it looses power it runs beautifully, no hesitations or anything, but faithfully when it reaches that 4800 mark it has issues.

Any suggestions would be greatly appreciated!!

leaky vacuum chamber or leaky check valve going to vacuum change that check valve fist thing, it is the only one between the UIM and the firewall, should improve things a bit. also could be wastegate actuator, check that rod and make sure its not stuck

Thanks, Ill have to check those tomorrow...

My guess is that the Turbo control solenoid is defective or incorrectly plumbed.

i had the same problem a while back and i tested my solenoid, it was fine, but yes, yours could be bad

I just purchased a stock one as well. It's boosting 10-8-8.

Any ideas ?

:-) neil