Boost leak questions

[68442]

I've got my leaks found, just a few questions. They are all in the throttle body. 1st and biggest is the pcv valve, it'll hold 15 psi when the tube from the intake is plugged. 3rd is the base idle screw which bubbles, plugging with my thumb doesn't allow the psi to build any higher. Pvc should be a easy fix but I thought with the throttle body blades closed nothing should get into the intake?

 

[97gsx_zeclipse]

my biss leaks too but i have no idea to fix that. As for the PCV valve you should get a check valve between it and the mani. Solved my problem and not bad for 2 bucks.

 

[kmoore]

For the PCV valve, just go and get an OEM replacement. It is bad and it needs replacing.

For the BISS screw, all that needs replacing would be the o ring that is located underneath the screw itself.

And my guess would be that your throttle body shaft seals are also shot. To replace those though requires a little more work. Although, easy to do, it is complex. Search throttle body shaft seals and you'll find some how to's.

 

[romeen]

For the BISS o-ring, go to any hardware store and get a 1/4" o-ring for a few cents. This will be just a hair thicker than the OEM one which I think is good because it makes a tighter seal. Dab a little grease (like dielectric) on the o-ring before install. You'll never worry about that again. Hardest part is getting the damn BISS out.

As mentioned get the inline check valve to solve PCV leak. Even many brand new OEM ones leak.

http://www.dsmtuners.com/forums/newbie-forum/229338-stupid-pcv-question.html

 

[tunethis]

I've fixed most of my boost leaks recently. Funny thing is, I ordered a OEM PCV and it leaked from 1psi on. I put my advance auto parts pcv back in there and it held 17psi. It probably holds more but the leak tester popped off the throttle body elbow. Your best bet is to get the plastic check valve because a PCV valve may or may not leak at your boost level. For the biss, screw it all the way down while counting the turns. That way, you'll be able to put it back exactly where it was after installing the new o-ring. To remove the biss, you unscrew it all the way then send some air through the system (boost leak test) and have some way of catching the biss screw as it pops out. Good luck.

 

[romeen]

To remove the biss, you unscrew it all the way then send some air through the system (boost leak test) and have some way of catching the biss screw as it pops out. Good luck.

How come I never thought of that.