P0440 Code Tip

[kephas]

A tip to help people like me out there:

For the past year, I was getting an intermittent P0440 code. This is a very vague code that indicates a general EVAP system malfunction.

Just realized today that the solenoid on the canister in the engine bay was unplugged. Did some work on the brake lines earlier this year and never plugged it back in

So, if you ever have this code, make sure everything is plugged in.

 

[movietvet]

Welcome to the forum from Oregon.

Before you found that unplugged, how many times did you tighten the fuel fill cap or replace it?

 

[lbeninger]

Welcome to the forum from Oregon.

Before you found that unplugged, how many times did you tighten the fuel fill cap or replace it?

I would have done the same.

 

[Road Trip]

A tip to help people like me out there:

For the past year, I was getting an intermittent P0440 code. This is a very vague code that indicates a general EVAP system malfunction.

Just realized today that the solenoid on the canister in the engine bay was unplugged. Did some work on the brake lines earlier this year and never plugged it back in

So, if you ever have this code, make sure everything is plugged in.

Welcome to the GMT400 forum from the finger lakes region of upstate NY.
BTW, your post sharing your self-inflicted P0440 experience was a great way to
introduce yourself.

Once you figure out the lay of the land, take a few photos of your '99 Suburban
and post them by starting a new thread in the Member's Trucks section. Note: Photos
are very popular, and they don't relent until you upload them. :0)

Enjoy this place -- lot's of solid, helpful folks in here.

Cheers --

 

[kephas]

Thanks for the warm welcome all!

Hadn't tried replacing the fuel cap yet, but definitely would have if I hadn't been lucky and seen my mistake.

Will upload some pics soon.

 

[Tan1998K2500]

Ironically, I had done the same thing with my truck. I forgot why I unplugged the evap solenoid but I did. Had very intermittent p0440. I replaced the valve on the manifold thinking it was going bad because it didn't look the best anyways. Very shortly after, I got the code again. I looked around the engine bay and found a random connector not connected and then saw the solenoid was unplugged

 

[_rgk]

Lord almighty. Same here. Thank you!