Failed Emissions

[d21 4x4]

Well, I took the D21 to emissions and everything went great, until the pressure test. :shaking: The tank holds pressure, but it doesn't release it. Someone said the replace the check valve near the fuel tank. Has anyone heard of this?? :confused: Any info on this would definitely help. Thanks, Tim

[System-f]

what year is your truck? OBDII systems have all kinds of doo-hickies for the EVAP system and I have had to replace most of them on my 98 pathfinder. I think all post OBDII systems just had the charcoal canister under the hood??

[d21 4x4]

It's an 89 D21 4x4 V-6

[System-f]

it should have simple underhood EVAP equipment. It's very possible the charcoal canister is shot, one of the lines from the gas tank to the engine compartment is cracked or the filler hose is cracked?

[jonx4x4]

Well, it would seem to me if it will hold pressure, but not release it, then it would be a plugged hose, or a plugged charcoal canister.