Code PO440

**00 formula** · 12-04-2008, 09:14 AM

I know it refers to a fuel evap leak... need to know how serious and possible causes if the gas cap/ seal are fine?

This is for an 01 cavalier.

Thanks in advance for any advice.

**2001NBMZ28** · 12-04-2008, 09:25 AM

Are you sure the seal is fine? My girlfriend's cavalier kept throwing the same code until I replaced the cap with a new one, even though the seal looked good.

**00 formula** · 12-04-2008, 09:30 AM

Originally Posted by 2001NBMZ28

Are you sure the seal is fine? My girlfriend's cavalier kept throwing the same code until I replaced the cap with a new one, even though the seal looked good.

not positive but it looks good so far, I'm reseting the comp and seeing if it comes back on but wanted some ideas in case it does.

**2001NBMZ28** · 12-04-2008, 09:38 AM

Hers started coming on every week and I kept clearing the codes. Luckily the cap fixed it and it wasn't something else in the evap system like the purge valve, canister, etc.

**00 formula** · 12-04-2008, 09:41 AM

Originally Posted by 2001NBMZ28

Hers started coming on every week and I kept clearing the codes. Luckily the cap fixed it and it wasn't something else in the evap system like the purge valve, canister, etc.

I'll have to try that first and foremost.