if i drive 3miles and stop strong oder of gas by the cap and charchol can under the cap filler line let it sit and the code goes away by it self some times po 440 comes up on my scanneri must reset it often.....no visable leaks any where on any lines but all ways fuel smell can anyone help......thanks ...pete have changed the cap several times so the cap is new and on the right amount of clicks......thanks

 

Don't know if this will help BUT on my '96 Blazer I had EVAP codes and replaced the EVAP solenoid that attaches directly to the engine. No help there as the code (I think it was a P04XX) came back. I did a little research on the EVAP system and was able to finally find anothe solenoid in the system that solved my problem. There is a solenoid valve tucked above the spare tire carrier in the rear of the vehicle. The solenoid opens (when the computer tells it to) to allow fuel vapors to get sucked into the engine to be burned. It attaches to the charcoal canister thru a single rubber hose. Bought a new one ($35.00) at the dealer and wha-la, no more code. Good Luck.

 

Pete,

try this link for information:

http://www.obd-codes.com/trouble_cod...alfunction.php

You may have a bad "purge control valve". Mine was tucked above the spare tire carrier of the blazer. An easy fix once you find the little bugger.