Canadian resident ,bought my catera used in nov.2003...in febuary 2004 had to change valve cover gasket after engine emptied of its oil ,after starting engine in - 25 ' celcieus weather...again on dec.22 2004 gasket blow out engine oil pours out on -28 ' celcius weather ...this time i am being told that problem is due to pvc seperator that froze .so would net let pressure in crankcase exit engine ...has any body ever heard of this problem ? can you tell me if possible (cause and effect) ? could it be caused by another problem ? if so what ? even if its the pcv valve that freeze's what guaranty this will not happen the next time temperature drops below -25' ? need help and aswers. Thanks The kid

I know that not having a functional PCV valve can blow seals in the engine and this might just be the case. Have they replaced the gasket seals on the valve covers or the valve covers, or both? Having bad seals and at that temperature may be an issue.

Check procedure:

Disconnect the CV vacuum hose.
1.Start the engine.
2.Check for vacuum at the hose. If there is no vacuum, check for a plugged hose or a plugged manifold port. Check for a hose that collapses when blocked (vacuum applied). Replace the plugged or deteriorated hoses.
3.Allow the engine to idle at the normal operating temperature.
4.Remove the engine oil dipstick and install a vacuum gauge on the dipstick tube.
5.Block off the CV system fresh air intake passage.
6.Run the engine at 1500 RPM for 30 seconds, then read the vacuum gauge while the engine is running at 1500 RPM.

If a vacuum is present, the crankcase ventilation system is functioning properly. No vacuum indicates that the engine may not be sealed and is drawing in outside air. Check the valve covers, the oil pan gasket, or other sealing areas for leaks. If the vacuum gauge registers a pressure or if the vacuum gauge is pushed out of the dipstick tube, check for a plugged CV housing, a plugged hose or for excessive engine blow-by.

It sounds like it is what your mechanic suggests.

Reply to Jeffrey.

Have replaced valve covers and gaskets...have also changed pcv seperator
part number 90502186 ... are you aware of any technical bulletin's emited by GM to its dealer's regarding possible problems with this part in cold weather?

And could you tell me what primary fonction a pcv valve has on my or anyother car ? is the primary fonction of the pcv to permit evacuation of pressure from engine or to recycle oil vapors?can a car operate without a pcv seperator or would engine blow seals every time you would start it if it does not have a pcv seperator ?

Thanks for your help with my questions
The kid