i have a 98 chevy blazer 4 doors with normal problem but i being able to fix most of them, not all of them.
i have check the whole system for leaks and can't find any i also replace the evap charcoal canister and i still get check engine code p0440. gas odor are near the gas door on the outside and inside too but i can't find any leaks.:frown:

Welcome Aboard!

Have you tried a different cap yet? The 'O' ring or the vent valve could be damaged.

Welcome Aboard!

Have you tried a different cap yet? The 'O' ring or the vent valve could be damaged.

this is my third gas cap i got the first two from autozone and pepboys and the last one i got it from the dealear.

how could i check the O ring and the vent valve.

I had this code on my 99 blazer 4x4 4 door. There is a module at the back of the gas tank, ( back of gas tank and front of spare tire on my blazer). If i remember right there are two hoses and one electricial plug to it. Replaced it (35.00) Problem gone. Hope this helps.

Boomer,
Thank You for Posting your truck's P0440 FIX............

I think it's called a purge solenoid. We replaced one on a family members 97 Blazer last year and his P0446 code has not returned, I think he got one for $12.00 on the internet....

(Thanks again for your help last year MT2500)

Dino...

I finaly got the EVAP problem fix, once I drop the gas tank i found a disconected fuel hose. The hose wasn't clamp two years ago when a shop replace my fuel pump and with time it disconected it self. i also replace the O ring on the fuel pump. :)