PVC valve is the small valve connected by hose to the
back of the valve cover.
It is very common for the EGR valve to be stuck
slightly open and allowing exhaust to enter
intake manifold when idling and cold. Normally,
the ECU holds off EGR circulation with the EGR VSV
valve and EGR Vacuum Modulator until conditions
are good for taking exhaust gas. But, if the EGR valve is sticking, the computer cannot compensate
and it idles rough. It is easy to remove the EGR valve, but a bear to clean it. It has a long tube that goes inside the manifold. I use carb/choke cleaner (you may need a couple of cans, but it's cheaper than a new valve at $190).
I hope this helps.
Tuesday, July 24th, 2007 AT 1:13 AM