Anyone have any tips for me to use on this code? I looked under truck and all hoses to/from tank to EVAP canister look/feel OK. Checked gas cap and it seals under pressure.

I did find a small spiral crack in the plastic insert at the filler neck entrance and was able to super glue it closed. It could have allowed some air to escape the cap seal, but not sure how much.
If this is not the source of the code, where else should I start looking.

FYI 99 F150 4.6

Thanks
Dialtone

 

Best bet is to locate a shop that has a "smoke machine'.

Trying to diagnose a small leak (<.040") without the correct test equipment will be extraordianally difficult.

Steve