Finally Boosting Like It Was Intended, 9 months after my swap Options

[jgreening]

Last night we were finally able to find two problems in my boost / vacuum system that had been preventing me from boosting properly all the time (the problems were intermittent). The first problem was that I had a chewed O-ring on one of the injectors which was letting a small amount of air out. We replaced the O-ring and the leaking stopped when we pressured the positive boost system. However, that did not cure my huge vaccuum deficiency. We were wildly speculating about the cause of the problem which included possible defects in the head (read: $$$) or other issues. We did a compression test which turned out good. But, the shop did not have a leak down tester. We were just about ready to give up for the night when my mechanic said he wanted to switch my boost guage out with a mechanical unit. I was tired and ready to go home and I told him that it wasn't the guage because the car boosted properly on an intermittent basis and when it worked, the boost guage worked. I told him that if the guage was bad, there would not be a corresponding increase in horsepower when the guage decided to work correctly. I actually offered to bet him $5.

He took the guage out of another car and hooked it up to my vacuum hose connected to the BOV. When the car was started, it showed a vacuum of 20 h/g!!!!!!! My electronic guage was showing a h/g of 6! Sure enough, it was the guage that was defective. Do you believe it? Another problem solved by identifying a defective Autometer guage. Thats number 2 for me.

The reason that there was a corresponding increase in horsepower is because when the guage was reading incorrectly, the boost was alot lower. I have really been driving around on about 7psi for the last seven months. The car is sooooo different at even 10 or 12 psi.

[jgreening]

I think I will keep it at about 10-12 psi until I replace the guage. I am really guessing at what the boost is since the guage reads incorrectly. I ordered a mechanical Autometer (to match my other guages) last night from JEG's so it should be here shortly.

The car feels so incredibly different with higher boost. Its really amazing and difficult to describe to someone who hasn't experienced it.

I forgot to mention something. My injector clips were red and not black! We wrote down the part number and are going to find out what they are. I have read a few posts on mr2oc.com that indicated the ST205 injectors have red clips.....I might actually have 540's in there! That would be great because I plan to upgrade to a larger turbo after my exterior mods are finished (GT28RS). I will keep you informed.

I will see what I can do about a video of the engine bay for you Art.