I have a 2001 Blazer and saw a lot of others with the same type of issue. It started with my check engine light coming on after I purchased it back in Jan of this year. It was the P0440 (evap system). So far I replaced the following:

gas cap
EVAP vent solenoid
Vapor Canister Purge Valve

My check engine light is still on. One other note. When I fill up with gas the pump stops (like the tank is full) even though the tank is empty. Usually it does this a couple times as I'm filling. Any help is appreciated.

 

2 or 4 door? 2 or 4WD? If 4 door, plastic or steel fuel tank?

 

4 door with 4wd. Not sure about the gas tank. I'd have to check into that.

 

Follow the steps in this link, and it will take you to the P0440 problem: https://blazerforum.com/forum/diagno...plained-35145/


We need to know which tank you have, to help you with the refueling issue.

 

Just checked... It's a plastic tank.

 

The refueling issue is most likely due to the anti-siphon ball in the filler neck being stuck. If it is present, remove it. Some do not have the ball and instead have a valve in the filler inlet of the tank, and it will jamb or bind. Needs to be freed up or removed.

 

Thanks for the info. Would that throw the service engine code?

 

I had that dreaded 0440, turned out being the filler neck was bad, replaced that, no more code, and I literally just removed my anti siphon cage/ball, fueled up with no issues after that. Really easy to get to as well, just peel back that little flap on the driver side rear wheel well, pull off the big fuel hose, the ball should be right at the end of the neck, wd40 helped me to get the hose back on when i was done, slid really nice over the filler neck.

 

There are several things that can set the DTC and turn the light on. You need to follow the flow chart in the link to find out exactly what turned it on.


The anti siphon ball on your 4 door, might be in the filler neck, or there might be a "check valve" of sorts in the neck of the tank. All 2 doors have the anti siphon ball in the filler neck.

 

Thanks for all the tips. Really appreciate it.