Boost Leak (Pressure) Test

[husterka]

I am giving my 99 eclipse GSX a good tuneup before I begin to spend money on mods for it. I have changed the plugs, wires, timing belt, and PCV valve. I have also checked / changed all filters. Is there anything that I missed??? Also, I want to perform a boost leak test and I need to know exactly how to do this. I have made the intake adapter and have tried testing the system. I am using a bicycle pump to pressurize the system and as soon as I stop pumping, I can hear air escaping somewhere near the throttle body (side farthest from the IC pipe). I had read somewhere that you need to block off your EGR valve and also bring your engine to TDC in order to properly do this test or else the pressure will simply leak through the engine and out to the exhaust. Is this true???

If anyone has a fully detailed method for performing this test (preferably on a 2G) please post it here. Thanks!!!

 

[GoSpeedRacerGo]

www.vfaq.com

 

[MitsuReaper]

Originally posted by husterka
I am giving my 99 eclipse GSX a good tuneup before I begin to spend money on mods for it. I have changed the plugs, wires, timing belt, and PCV valve. I have also checked / changed all filters. Is there anything that I missed??? Also, I want to perform a boost leak test and I need to know exactly how to do this. I have made the intake adapter and have tried testing the system. I am using a bicycle pump to pressurize the system and as soon as I stop pumping, I can hear air escaping somewhere near the throttle body (side farthest from the IC pipe). I had read somewhere that you need to block off your EGR valve and also bring your engine to TDC in order to properly do this test or else the pressure will simply leak through the engine and out to the exhaust. Is this true???

If anyone has a fully detailed method for performing this test (preferably on a 2G) please post it here. Thanks!!!

a bicycle pump? ehhehe.

you are doing it right. just pump the system up.
it helps to hook up a compressor and set the regulator @ 15 psi.

then listen for leaks.. the leak at the TB everyone has. unless they have replaced the gaskets. (not the TB to intake gasket)

 

[irn__man]

Originally posted by MitsuReaper


a bicycle pump? ehhehe.

you are doing it right. just pump the system up.
it helps to hook up a compressor and set the regulator @ 15 psi.

then listen for leaks.. the leak at the TB everyone has. unless they have replaced the gaskets. (not the TB to intake gasket)

MitsuReaper,

Yeah, I just spent about 2 hrs pressure testing my 99 GSX. Here is the leaks I found. 1st was Greddy BOV Flange Gasket (sucks had to make my own), 2nd was bad weld on UIC piping (will post thread so others can be aware), 3rd was gasket where UIC connects to throttle body (still leaks need new gasket).

So, if I replace the throttle body gasket I should be all set. I guess those gaskets are not reusable.

later
iron

Oh Yeah! As far a blocking off any EGR Valve, I did not have to. I just took my MBC out of the picture and plugged the outlet for BOV. Easy enough a Air Compressor is the way to go, screw using a Hand Pump.

iron

 

[MitsuReaper]

the greddy gasket that you made... is it out of cork or something?

if its not, you can just smack a little RTV silicone on it, and it will seal fine.

same with teh TB elbow gasket.

 

[irn__man]

Originally posted by MitsuReaper
the greddy gasket that you made... is it out of cork or something?

if its not, you can just smack a little RTV silicone on it, and it will seal fine.

same with teh TB elbow gasket.

BOV gasket I made out of some Hi-Temp rubber that I got from work. I figured it would just be temporary until I have a chance to make the gasket out of something else. I can give the RTV a try, I will also try it on the throttle body.

thanks for the tip

iron

 

[Silent2g]

to fix the elbow leak
get rid of the studs for one, get two matching bolts
place a THIN layer of black rtv on both sides of the gasket {thin enough you can see through but still be sticky}

torque the piss out of all four bolts. do opposite corners first {like putting wheels on}

baby the car for a couple days {this means no boost}

also put some silicon ontop of the BISS sset screw {major leak for me}

clamp the piss out of the pcv valve hose