I was conducting a boost leak test on my car today and I started getting air out of my Oil filler cap. This was followed by a release of air from the back of the engine, PCV Valve? My question is why would I get pressurized air in the crankcase?

Now when I idle the car and drive it I am getting some white smoke, very faint, out the tailpipe. Could the PCV valve be gone and cause this? Did I somehow push oil somewhere it shouldn't?

ANy help is appreciated.

 

how much boost have you been running lately? Did you upgrade to arp studs? You may have blown the headgasket...

 

Definatly sounds like you blew the PCV valve into a constant "open" state, or something. How much pressure did you use to do the test?

 

Was running the test to 15-20 psi. Anyone have the PCV valve part number?

 

No part number, but the next best thing?

http://www.trademotion.com/partlocat...layCatalogid=0

 

MD152772

 

Is it mandatory or recommended to replace the PCV Valve Hose at the same time? Thanks Razor the part number above.

 

You'd get pressurized air in the crank case through:
Valve guides
Piston rings
Turbo oil seals

It would escape through oil cap, valve cover gasket and exhaust.

All that is normal to some extent. And it can't go out through PCV, because PCV is connected to a pressurized manifold. Unless you have it vented or something..

And you said Raxor

 

Fixed the spelling error. Mplspilot, what you are saying makes sense, kinda, when testing, but why am I still getting the oil smoke while driving. I have done boost leak tests on my car upt to 25psi and not had this issue. Now at 15-20psi, I get air out the oil cap and a hissing behind the engine. I figure maybe the PCV or a line back there, not sure.

 

Sure its not the Throttle Body Leaking? They are notorious for that. Mine leaks at the moment too lol

 

Well white smoke is usually coolant.. Which as it was mentioned before usually means head gasket issue. Or it may be from the turbo i suppose, but i'm not sure on that one and if it's at all possible to leak coolant through the hotside, someone else would have to chime in..

You should try to find out where exactly the air is coming out of. Back of the engine is a bit too vague..

 

Yeah couldn't find it. The wierd thing is the smoke smells like oil burning. I will do some more digging tonight.

 

Not sure if EVO's have oil caps like DSM's, but you can usually double the gasket up on the underside of them to prevent the crankcase pressure from blowing out of the oil cap.

 

Replaced the PCV valve and the problem has disappeared.

 

i got to do a boost leak test on my car. anything up to 20psi car is fine. after 20psi all the way to 26 psi i got a loud poof/poping sound of air come from under the hood. all clamps and hoses are perfect and tight. so it could be the throttle body shafts seal or pcv valve is bad. I do smell kinda burning oil exhaust smell when i come to a light. idle before was -14psi and now at idle -11psi. and the popping sound is getting worse and worse. how do you got a leak test.