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2005 saab 9_7x
5 Posts
Discussion Starter #1
I've solved this, but couldn't find this information on the interwebs all in one spot. I gleaned info from multiple sources and took an educated guess. In case you have the following symptoms, keep reading:
  • Trouble starting after filling up--engine turns over and then immediately stalls; once fuel level is approximately 3/4 or lower, starting is reliable; adding any fuel to tank seems to make one stalled start, then good (depending on fuel level)
  • "Tighten Gas Cap" on dash display
  • CEL
  • P0496 "EVAP Flow During a Non-Purge Condition"
  • P0172 "System Too Rich (Bank 1)"
  • P0175 "Engine Too Rich (Bank 2)"
  • P0455 "Evap System Large Leak Detected"
  • P0456 "Evap System Small Leak Detected"
  • Did I notice a decrease in fuel efficiency? Not really sure.
I replaced the Vapor Canister Purge Valve/Solenoid. This one $16 part fixed all the above symptoms. ACDelco 214-1680. Procedural tips follow:

Disconnect the battery first.

If you are not able to successfully remove the electrical connector for the Purge Valve by gently lifting the locking tab, you will need an ACDelco PT2784, 2-wire male connector, $15. Re-assembly is merely pushing the connector on the Purge Valve.

If you don't use needle nose pliers to squeeze the tiny black tab to the stop on the circumference of the connector on the Vapor Canister Vent Hose when you disassemble, you will probably need a new hose, ACDelco 12574897, $22. That little black tab is only visible/accessible on the Purge Valve's connector once you remove the same connector on the opposite end of the hose which is on the top of the engine; then, rotate this hose about 90 degrees and you'll see the tab to release the connector from the Purge Valve. However, the alternator is in the way to back this hose connector off the Purge Valve. You'll have to wait until the Purge Valve is removed from its bracket before you can fully remove this connector. Don't forget to push this connector back on the Purge Valve before sliding the new Purge Valve on the bracket, or else you'll have to slide the Purge Valve back off the bracket again.

If your vehicle is old, the little white plastic lock on the Vapor Canister Purge Valve Hose will break no matter what you do, including merely touching it. In that case, you'll need an ACDelco 12658354, Vapor Canister Purge Valve Hose, $12. Or, if you have tiny zip ties available, you can simply insert one where the white plastic lock was and be done with it when you are ready to reconnect. It's also possible the hose is stiff enough without falling off for you to drive to Wally Mart in order to purchase a bag of small zip ties.

Be very careful in using a flat bladed screwdriver to push open the locking tab on the bracket in order to remove the Purge Valve. Since this part is metal, hopefully it doesn't break on you. I couldn't find a part number for this bracket. When re-assembling, you may need to push that metal locking tab back into place on the Purge Valve.

After reattaching the Purge Valve and reconnecting the battery, start the engine. All the codes and CEL will still be there, unless you took long enough for the codes to clear with the battery disconnected. Clear the codes with your scanner, and you're all done. I'm pretty sure most (if not all) of the codes will go away after a few start cycles, or disconnecting the battery for a longer time.
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