Anyone that can disagnose my Check Engine Light? P0442

[kelemvor]

Just updating this post since I went to AutoZone and was told I had a P0442 error. The guy said that this means I had an exhaust leak somewhere before the last Oxygen sensor and I should have an exhaust place look at it to try to find the leak.

I already tried a new gas cap but that didn't help. Check Engine light has been on for a month or two and I don't notice anything different about the car running...

UPDATE: Woo Hoo. Got it reset last night at Autozone when they read the coed and it still hasn't gone back on yet. Went to get Emissions tested and it passed. I'm sure it will come back on eventually but I don't care for another 2 years.

[SE2000]

If advanced auto hooked it up to their machine, it either gave a code which if you tell us, we could give suggestions. If they did not get a code, then it's not likely anyone here has a high end machine at home. If you have emissions problems, have you tried ALL the hoses?

[kelemvor]

Going to AutoZone after work today. They said they can give me the code I need (hopefully) Will post more when I get home.

[mattcow]

Let us know, I have had a small leak for a while that I can't track down.

[kelemvor]

Well, I stopped at AutoZone and I think the code I saw on the thing was P0442 (i wrote it down and left the note in the car). THe guy said that this mean there was a leak in my exhaust system somewhere before the last O2 sensor and I should go to an exhaust place and see if they can find it.

So I guess I'll have to call some place to see if I can get in for a free estimate and go from there.

[carlover626]

That code means:
P0442 Evaporative Emission Control System Leak Detected (small leak)
I believe that could also be the Gas cap or related??

[rixGAphx]

Originally posted by kelemvor
..I think the code I saw on the thing was P0442 (i wrote it down and left the note in the car).
The guy said that this meant there was a leak in my exhaust system somewhere before the last O2 sensor and I should go to an exhaust place and see if they can find it. Before you do anything else, PLEASE read your note and tell us EXACTLY what code number was scanned from your car.

Because, as carlover said, P0442 is a small leak in the EVAP system; this is all relative to the Intake manifold, and evaporation of liquid gasoline.

This has NOTHING whatsoever to do what the "guy said that this meant there was a leak in my exhaust system somewhere before the last O2 sensor"!!!

Right now, the data from you are absolutely contradictory, and we need to clear that up.
The guy might have been an idiot, or he might have gotten a different code than P0442 (like P0422 -Main Catalyst Efficiency Below Threshold, which is cat/O2 related).

Don't go to an exhaust shop for this P0442 non-exhaust code.

Standing by,
-Rick

[BPBAIR]

I had an 0442, and talked to my mechanic about two weeks ago. He told me that, when he worked for pontiac last year, he used to get small evap leaks all the time. He said if its not the gas cap, it will almost certainly be the ring seal by the fuel pump on the Grand Am. He said that they were so common that they just stopped doing smoke tests and started replacing the seals. They have to drop the gas tank to gain access to this tho. Might be better off just buying a code reader and clearing the code. He told that he has never seen it become a large leak.

PS: alot of the fuel system's parts are being eaten up by the new ethanol additives that were slated to start this summer instead of MBTH, which was bad for the environment.

[kelemvor]

OK, I checked my sheet and it was a P0442 that I saw on the scanner thing. And that is what he told me about the O2 sensor thing.

I know it's not the gas cap because we already tried going that route and it didn't help.

He did clear the code for me so if it doesn't go back on on my way to work tomorrow I'll go n for testing at lunch and hope everything comes out OK.

Otherwise I guess we'll just see what happens.

[kelemvor]

Thanks for the info everyone... See the info in the OP. I guess now I don't really care so much. ;)

[kyboman]

I get the same code often on my 99 Malibu. Changed the gas cap and it still comes back, but not as frequent. I get the code when the tank is below 1/4. This makdes me agree with the fuel pump seal idea. Low fuel, lots of vapors to leak. Never seem to get the code with a full tank of gas. I checked all the hoses going to the canister under the fuel tank and lall OK. I bought a cheap actron code reader to erase the code when it happens and I keep the tank above 1/2.

With a '99 and 100K it shouldn't be long before I have to change the fuel pump and this leaky gasket.