PO442 code

[brute]

Our 1997 Grand Am GT (3100) keeps having a reacurring code PO442. Have changed the gas cap with new, my question is, the fuel tank when filled has a slight leak ,probrably top o-ring , could this cause the code? Have visually checked all hoses etc. Any ideas?:(

[bandit307]

I personally would get the leak pin pointed and fixed. Zero tolerance when it comes to any kind of fluid leak period. Sorry i cant be of much help though.

[Nighthawk243]

Yep. Patch the tank, pronto.

[SE2000]

Leak in tank would be like a loose gascap to the computer

[rixGAphx]

Originally posted by brute
... the fuel tank when filled has a slight leak, probrably top o-ring, .... As SE2000 stated, a leak is a leak to the PCM, so it'll throw the same code.

Are you saying there is gasoline leaking from the top of the tank when you fill-up?
That's dangerous and should be reapired immediately.

My question is, why do you suspect the O-ring on the fuel pump as the leak source?
There's no reason for the O-ring itself to fail.

I've dealt with Jeeps, where the screw-down sealing ring 'pops' loose and allows the kind of leak you describe.
But the GA's tank and pump are a different design, so this unique Jeep condition won't occur.

IMO, it is just as likely that the top of your tank has rusted-thru at some spot.
It may even be allowing a little water IN from time to time :eek:

Anyhow, step one is of course to use the gasoline up, then,
Step two is to drop the tank and find the leak.
This problem is never going to get better by itself, and could soon result in a disaster if not fixed.

Good luck,
-Rick

[BPBAIR]

ok i have that same small evap leak, the light for me only turns on when the tank dips below a 1/4 full. if i keep it full the light stays off, less fuel vapor to escape i guess... goodluck thats all i can offer