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derekderek
04-07-2006, 02:54 PM
Well I have a 92 gsx. I have a major boost leak. I have eliminated most of the leaks have found. But there is still one left. When I hook up to the TB I can't hold past 5-7 psi the throttle body is not leaking itself and the intake manifold gasket is not leaking . I know the injector's could be leaking but when I spray them down I do not see any bubble's. Is there anything else I should be looking for that might leak? Also at about 4500-5500 rpm the car starts to sputter but i am guessing this is because the boost leak well thanks for the help.

v413nc3
04-07-2006, 02:58 PM
Ok, I'm trying to follow what you are saying. When you disconnect your Upper Intercooler Piping (UICP), and connect a coupler with a compressed air hose to the throttle body you can only hold <10PSI? The intake gasket is not leaking, nor is the throttle body/gasket. If you have ruled out the injectors I would say check all your hose nipples. There is a rather large one that goes to your brake booster that should be checked as well. The only hangup I have on this advice is you should be able to hear the hissing. What is the pressure of the air you are inducing? Normally you should test with between 15-30PSI. At that pressure you should definately hear the leak.

derekderek
04-07-2006, 03:09 PM
You are correct when I hook up to the throttlebody I can only hold 5-7 psi. Everything before that holds 20 psi fine for 30-45 sec before it starts to leakdown. I am at a lost with this could my valves be leaking the air out? On my boost guage I am only reading 10hg at idle on coastdown 15hg. I will check the brake hose I remember seeing it and it sliped my mind. As for the pump I am using the basic electric tire pump that hooks up to your cig lighter. Thanks for the help i really need it.

Mirage
04-07-2006, 03:29 PM
You need to get a compressor or an air tank that has some sort of flow.

There are natural leaks through the rings and through open valves.

I'm amazed that small air compressor actually created that much pressure in the system.

Get something that you can regulate to 25 psi (for your application), connect it to the turbo inlet, and test for external leaks that way.

Marcus

sbiggi
04-07-2006, 03:31 PM
You are correct when I hook up to the throttlebody I can only hold 5-7 psi. Everything before that holds 20 psi fine for 30-45 sec before it starts to leakdown. I am at a lost with this could my valves be leaking the air out? On my boost guage I am only reading 10hg at idle on coastdown 15hg. I will check the brake hose I remember seeing it and it sliped my mind. As for the pump I am using the basic electric tire pump that hooks up to your cig lighter. Thanks for the help i really need it.

You engine vacumm is normal.

derekderek
04-07-2006, 03:37 PM
Ok thanks for the help I will get a airtank our something and fill it up with air and try that. I have one more question. The timing marks on the cam gears should line up in the middle facing each other? Well mine arent the back one will be in the middle lined up facing forward and the front cam will be facing 180degrees the other way. I hope I explained it enough. Well thanks for the help. I am new to dsm's so thats why I am asking all the questions.

wolf20043
04-07-2006, 03:40 PM
Ok thanks for the help I will get a airtank our something and fill it up with air and try that. I have one more question. The timing marks on the cam gears should line up in the middle facing each other? Well mine arent the back one will be in the middle lined up facing forward and the front cam will be facing 180degrees the other way. I hope I explained it enough. Well thanks for the help. I am new to dsm's so thats why I am asking all the questions.
Just make sure at TDC both cam dowel pins are at 12 o clock. I have seen the gears have only one mark on them, and two as well to form a straight line.
Mike

fusionsport
04-07-2006, 06:45 PM
While 12 o'clock is "safe" you can actually be a little off depending on the cams used, assuming you are using factory cams. Mitsubishis instructions are to align the marks in the gears with the cylinder head surface. I believe this is because as they changed cams and adjusted lobe center it was easier to move marks on a gear than to change the pin location in a batch of billets. If you go by pin location its not really wrong, but may be completely right.

Hal
04-07-2006, 07:19 PM
Ok thanks for the help I will get a airtank our something and fill it up with air and try that. I have one more question. The timing marks on the cam gears should line up in the middle facing each other?

Yes, if they are factory gears.

The marks should be on the inside where the 2 gears are the closest together and the dowel pins on the cams should be straight up. If the marks are 180 off, it's ok as long as the dowel pins are straight up.

derekderek
04-07-2006, 10:05 PM
Ok guys thanks for the help the pins on the gears do line up at the 12 o'clock position. Thanks for the help with everything. I am kind of new to the Springs is there a shop that can tune your car around here? I have the maft+gm mas in the blow thru set-up but I do not have a datalogger,nor would I trust my tuning skills. Well thanks for all the help.