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evap emission


stinkyone
06-27-2007, 12:26 PM
Ok so i keep getting this code p0446 EVAP emission control system vent circuit malf but my truck isn't running bad. Where should i look for this problem, vapor canister? i have no clue and don't have much money to take it in right now. 1996 gmc jimmy 4dr 4.3

Rick Norwood
06-27-2007, 01:40 PM
Ok so i keep getting this code p0446 EVAP emission control system vent circuit malf but my truck isn't running bad. Where should i look for this problem, vapor canister? i have no clue and don't have much money to take it in right now. 1996 gmc jimmy 4dr 4.3

I am pretty sure that I had the same code which is basically a bad gas cap. Go buy a new one for about $10 USD. Don't forget to reset the system.

MT-2500
06-27-2007, 02:16 PM
Any other codes?
Check all hoses and vacuum lines on the system
First test is to clear code.
Remove gas cap and turn on key and read the fuel tank vacuum.
If it does not read 0 in h20 vacuum repair fuel tank vacuum sensor.
If it reads 0 in h20 with cap off it is going to take some more testing and test equipment to check it out.
Post back the reading.

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