suprafan

the history I put in a BCC, and profec B. I was unable to boost past aobut 15 with the profec wide open and was also having problems with what felt like intermittant boost cut and error code 35 I took it to the dealer and I disconnected my BCC and the error codes went away. My second turbo checkout with normal pressure. I rehooked my BCC today no error codes but I can't boost past aobut 12-14 psi again with profec supposedly wide open on high (about 10 with it on low). I have checked for a boost leak and everyting looks and sounds tight. the profec is hooked up the same as the blitz(non pt method) The car runs fine has great vacuum -30hg at idle ( would argue no leak since if there is a boost leak there should also be a vacuum leak) I have power to the profec. I have not done the last test ie pulling the hoses to the acutator to see how much boost I get with no control. any other ideas to test? do I have a bad profec? I suppose it is under warranty(bought it from Dusty at MVP) I am stumped and need the collected wisdom of the supra gods on this page Help

2jzhkstt

Just because you have good vacuum doesn't mean there isn't a boost leak. Remember, vacuum is coming from after the TB. Boost could be leaking from lets say the intercooler and you would still have good vacuum at idle.

About your -30 hg vacuum, it does seem really high. Tell me more about your car maybe I could help you.

__________________
T.C.

suprafan

okay it is a supra TT mods are exhasut DP, BCC and greddy profec B ( currently disabled) car idles and drives well had a problem with error code 35 when I recently put in the BCC the BCC was checked for voltage out put prior to putting it in( 4.2) I re installed it after the dealer checked out the car and have had no new error codes. I can get 10-11 psi but do not feel the transition to the 2nd turbo objectively with the waste gate disabled ( car should boost to 18+ because of BCC I only get 10-11. I had the dealer check out the 2nd turbo and they say I am making pressure with it so the problem has to be in the Vacuum circut that allows the transition to turbo number 2 either Iacv or egcv are bad is my guess I wish I new how to test them to see if this is the problem and just replace one not two.

suprafan

the story so far old fart decides to go BPU after many years. does it himself fouls up the BCC and corrects it unable to reach 18 psi thinks 2nd turbo FUBAR. checks with dealer who does pressure check 2nd turbo fine. Thinks i it may be actuator IACV or EGCV or a boost leak.
Okay guys just removed the twin Stock BOV no phew noises any more but a definte surge whent he 2 nd turbo kicks in still only boosting to 13-14 psi.

question I left the VSV hooked to the acutator of the waste gate but I left the t bleeder in with the tubes not completey pulled you will still get waste gate acuation right? I wanted to limit possiblities of error in as many variables as possible. So I now know my acutator and 2nd turbo are fine besides looking for any boost leaks I need to just diable the waste gate completely and do a run unfortunatly my road test schedual is over tonight and I got a meeting tomorrow night so next test is at 1900 hours on Tues. DZ out