View Full Version : Something strange with my boost (SR)

09-10-2006, 03:48 PM
I have a redtop with fp big t28, hks actuator, and nismo fpr. I have been boosting around 16psi for the past few months with no problems at all. I have had my fuel pressure set to 52psi with the Vaccume line on to compinsate since I don't have SAFC. I know thats not the right way to do it, but I'm broke and wanted to go fast. But back on subject, yesterday I was driving around, had no problems. Stopped at a stop light and my revvs went down to like 250 and the car was really trying to keep going. I gave it some gas and it perked back up to my set 800rpm without problem. Then I took off from the stop light in first and shifted to second. Got on it a bit in second and did not hear my bov go off. I slowed down a bit and got on it again, a little harder this time, and noticed that I was only at 10psi and my exhaust note changed slightly under boost, and when I let off I hear an air release from somewhere on the right side of my motor (bov is on the left). A side note, my bov has a stiffer spring in it and does not go off under 4k rpm (where I start boosting due to how rich I am running) or under 10psi. I need a new bov for sure.

I thought maybe the turbo was going to die, but I talked to a buddy I know and we noticed that the wastegate nut had backed itself off. So I adjusted it (to give more boost) and took it out for another drive and it was the same story.

We put air to the wastegate to see if it was opening and sealing which it seemed it was (without taking everything apart to physically see it).

Then we did a vaccume test. Unplugged the line going into the TB where my wastegate and FPR are hooked up to and did a vaccume test to find that something was leaking. Got rid of the FPR line and blocked it off, did the test again and it was fine. So we unplugged the wastegate and checked the FPR and it was leaking really fast. My fuel pressure has dropped slightly since I last remember and is at 49psi (though I may have changed it, but I can't recall). Could my fpr be bad causing my car to run less boost?

Thanks for the help...

09-10-2006, 05:59 PM
This is hard to diagnose over the net but here is some input from my dumb ass

1. Holy shit you gotta be runnin rich as fuck!!! You shouldnt be running more than 3 bar of Fuel

2. What injectors are you running?

3. Sounds like you have a Grommet or Coupler on one of your connections with a leak...check closely sometimes they are dry rot cracks that you can not see form just looking. Squeeze them and see if you see crack. Def could be a boost leak.