PO442 trouble code

09-24-2011, 01:19 PM
I have a 2000 Chevy Blazer 4wd 4 door LT. It keeps throwing code PO442 (x2). I have replaced the gas cap as suggested. What else can I check and where are the components located on the truck? Thanks for any help.

09-24-2011, 08:26 PM
P0442 is a small leak in the EVAP system, (.030" or smaller). The EVAP system consists of the following: Fuel tank, fuel tank module O ring, fuel tank pressure sensor & seal, purge canister, purge canister vent solenoid, purge control solenoid & seal, fuel tank filler neck & grommet, fuel tank vent line & grommet, fuel filler cap, fuel vapor lines from the tank to the vent solenoid, and up to the purge control solenoid. Those are all things that can and do leak. I probably missed a few items, but that should keep you busy for a while, or you can take it to a shop and have them hook up a smoke tester to find what's leaking.

09-26-2011, 05:00 PM
Make sure you got the right gas cap. My daughters car showed a code and she went to autozone to buy a gas cap.It helped a day or two and the could came back. Then she took it to a mechanic shop who put a tank sensor in it. That helped a day or two then the code came back. Then we took it to a dealer and they put it on the tester and changed the gas cap and it has worked fine sence. We told them we changed the gas cap and they said it was the wrong one. That ordeal cost here about 300.00 dollars because of autozones 7.00 mistake. Good look Fiserman

09-26-2011, 06:10 PM
well I have had the same code for awhile now...it all started when I paid a shop to change intake manifold gaskets due to leak....they said because it came on a couple weeks after the work they did it couldnt be there fault...still have not been able to track it down and cant afford to get a smoke test done...but I am sure its somewhere under the hood....sometimes it goes off for a few days and then comes back...

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