Boost Question Options

[oconnordaithi]

Hi All David her form Ireland! Just bought my second st205 after a long absence. It is a jdm model in silver hks air filter, blitz dump valvea and unknown exhaust. I got a bargain when I bought the car so all is well. The problem is that the car is not boosting as it should! When I floor it in third it will only go to 3/4 the way up eventually crawling to just under the line.... it never goes near the + as it should it also not near as fast as it should be. Turbo is reconditioned so its not that just had new plug leads and distributer fitted due to damaged lead. I reckon it must be leaking boost or something simple as car is very tight and not driven much. I'm no expert so I was hoping you guys could give me the benifit of you knowledge.
By the way great site lots of info

[presure2]

first thing i would do is buy a real boost gauge, the factory gauge is pretty much usless.
2nd thing would be to check for exhaust and intake leaks

[celicast3sgte]

stupid question but is the check engine light on? does it have an aftermarket boost controller?

This post has been edited by celicast3sgte: Oct 14, 2006 - 10:16 AM

[oconnordaithi]

no lights on dash no boost controller...... any suggestions?

[lagos]

you have a boost or vac leak somewhere. you can make a boost leak tester (google it) and find your leaks to fix the problem.

[Glitch001]

Tools required:

Air compressor with regulator
Drill
8mm socket and socket wrench
adjustable wrench
1/4" NPT tap

Shopping list for Home Depot:
2.5" - 4" (depending on turbo inlet size) PVC pipe plug
2.5" - 4" ( " " ) hose connection
2.5" - 4" ( " " ) hose clamp
1/8" NPT to air compressor hose connection

Many variations can be done with this setup, but the basic idea is to drill a hole in the PVC pipe plug and tap it for the air compressor hose connection. What matters is the inlet size of the turbocharger. My particular turbo (and most single turbo supras) has a 4 inch inlet, so I used 4" components, but someone with a CT26 would use a smaller plug.



You then attach the hose to the PVC plug and use one clamp to secure it in place, and the other to secure the hose to the inlet of the turbocharger.



Turn the pressure on your air compressor pressure regulator down to 20-30 psi, hook up the air hose, and listen/feel for leaks!

In addition, you MUST open the throttle body to check for leaks in your intake manifold and fuel rail grommets!

Special note for those that still have the factory idle air control valve. You WILL leak out of the factory IAC valve unless you supply power to the black with yellow stripe wire and ground to one of the other wires that go to the IAC. The easiest way to bypass doing the wiring is to take a pair of vice grips and block off the IAC valve air tube that goes back to the intake.


Thanks to Bryan for the writeup.

This post has been edited by Glitch001: Oct 14, 2006 - 5:29 PM

[oconnordaithi]

Thannx guys will keep u posted.......

David.