Rich exhaust?

I have been having a recurring problem with my 94 Grand Am. It has 149k miles, less than 60k on second engine, new just about everything. Well, after a rainy day in the driveway, it will start, but then starts to sputter and stall. It will keep doing this. I hit the gas to try to keep it running, but the service engine light comes on. The next morning it is usually ok, but not this last time. It has been to the dealer about 6 times, they keep saying there is nothing wrong since it runs fine for them. They misted the entire engine thinking it's a bare wire. But didn't find anything. They think I'm lying :nono: Last time they said it showed "rich exhaust" Didn't say it could or couldn't be fixed. Just sent me home because it was running. Well, I can't keep having this happen. Any ideas out there???? I really don't wanna get rid of my baby, she's got too many brand new parts. They also said it MIGHT be high oil pressure because Pontiacs do that? GRRR I'm ready to kick their tooshes for not helping me.

There are several items that could cause a rich exhaust. First the O2 sensor could be bad. This will put too much gas into the system and it will show up in the exhaust stream. Secondly, it could be that the convertor is going bad. They will not correctly clean the hydrocarbons from the exhaust and will show a rich condition. I would change the O2 sensor first and see if that corrects the problem. With regard to the sputtering after a rain. I would check the plug wires and get a little dielectric grease and put it inside all the plug boots as well as the boots where the wires connect to the coil pack. The fact that it only happens after a rain storm indicates that water it being absorbed in an area where the electrical connection is the most critical. You can get this grease at Autozone and do this yourself. If this doesn't work post again and I will try to come up with some other items to check.

What engine do you have?? the quad-4's have a coil pack housing that are prone to crack, and would cause a mis-fire when it's wet out. A mist with a spray bottle wouldn't be enough water to get down in and cause the misfire. If it's a v-6, the advice GTP dad gave is your solution minus one part. The rich exhaust may be caused by the unburnt fuel from trying to start it when it's acting up. There may not be a O2 problem, it's doing its job telling you the system is rich.

I DO have the quad-4. I should ask my mechanic about this, have him take a look. She's a good car, I want to fix her, not replace her. It's not a 6 cylinder, only a 4.

It's definately called "coil pack housing"? I have a book on my car and it doesn't list anything called that.

The other common name is a ignition coil housing or cover. The AC Delco part # is 10475706 and runs about $50. retail. There are also 4 boots off the bottom of this piece that connect to the plugs (they look like spark plug wire boots) and the Delco # is 12132224 and they run about $4 each. Replace these parts and your miss should go away.

Now that I did find, thanks. Even gave me the part numbers & prices, you're gooooood lol

I do my best, glad I could help