PCV Valve Test?

[jdeangelis]

I was doing some tuning and checking out how to test the PCV valves. The manuals say to remove the PCV hose and check for vaccum on each valve. The PCV valve closest to the firewall has a lot of vaccum. The valve closest to the grill has none. The hose doesn't have vaccum or pressure on it. It seems dead.

After looking at the schematic and trying to figure out how the system works, it appears this should be the case. This valve ties into the air plenum that goes into the turbo. If the turbo isn't spooling I wouldn't think there would be tremendous vaccum.

Is this true?

 

[bigtime]

Correct. Just replace them with new correct ones and go from there. Pay attention as they are different.

 

[jdeangelis]

Dofferent

Dofferent

They are both listed as the same part number in the AC Delco books. Do you know what the part numbers are?

 

[bigtime]

just take your vin# to the dealer and get them.

 

[Loeryder]

AC Delco 799C is the only PCV valve you should be using.

I believe it has the letter "E" stamped in teh bottom.

GM Part# is on my site
www.sytyauthority.net in the engine arena.

good luck