P0446 and P1450

[hotrod_chevyz]

Heres the codes im getting.


Problem 1: Troubleshooting code P0446

diagnostic equipment:

"The PCM has determined that a malfunction exists in the electrical circuit for the vent control in the evaporative emission control system".

Me:

"Say what? Does that mean my charcoal canister is bad?"


Problem 2 : Troubleshooting code P1450

diagnostic equipment:

"Unable to bleed up fuel tank vacuum".

ME:

I think i have a bad gas cap. I have noticed that the gas tank makes a noise often. It seems to me vacuum pressure is building in the tank and then the cap suddenly allows air into the tank after its built up a bunch. Half the time after it makes this noise as soon as you roll up to the next light it sputters, and dies. Also, when i take the gas cap off the car at a filling station, when i remove the cap i hear the tank take in a big breath of air. Could this be a possible explanation to the P1450 code?


What are these codes exactly, and what do i need to replace?

[fleettech]

chances are very good you have a bad cap. we have had a bunch go bad.

[hotrod_chevyz]

what about the P0446 code?

[reekor]

Sounds like a bad purge value or a plugged gas return line on both codes.

Originally Posted by hotrod_chevyz

Heres the codes im getting.


Problem 1: Troubleshooting code P0446

diagnostic equipment:

"The PCM has determined that a malfunction exists in the electrical circuit for the vent control in the evaporative emission control system".

Me:

"Say what? Does that mean my charcoal canister is bad?"


Problem 2 : Troubleshooting code P1450

diagnostic equipment:

"Unable to bleed up fuel tank vacuum".

ME:

I think i have a bad gas cap. I have noticed that the gas tank makes a noise often. It seems to me vacuum pressure is building in the tank and then the cap suddenly allows air into the tank after its built up a bunch. Half the time after it makes this noise as soon as you roll up to the next light it sputters, and dies. Also, when i take the gas cap off the car at a filling station, when i remove the cap i hear the tank take in a big breath of air. Could this be a possible explanation to the P1450 code?


What are these codes exactly, and what do i need to replace?

[hotrod_chevyz]

Update.

It wasnt the purge valve or canister. Or the gas cap. i thought i had it fixed when i changed out all three but eventually the CEL came back on. I havent had the codes scanned again as of yet but im sure its going to be the same problem. It must have a clog somewhere. Once i figure out what the problem is i will post it up for any who are wondering what can possibly set these codes. I guess i will unhook the line on both ends and shoot some air down them and see if its clogged.