The LIM gasket can go bad and NOT mix oil. It's luck of the draw on how the nylon brakes apart. Coolant follows the path of least resistance. I've seen where it forces coolant out through the seal and out of the engine all together (it may not be in high volume, but it does happen). One such case, found it using a radiator pressure tester (saw coolant bubbling out where the LIM and head meet). Hence why I would do a radiator pressure test before going further (even if you can't find the leak, if the tester does not HOLD pressure and it drops, you KNOW you have a leak still).

My experience with present day cars, the caps don't go bad (I'm sure they do, each time I thought it was a cap, I mis-diagnosed it and it was something else).

Now, if the bubbling you mentioned in an earlier post is a bad head gasket, this should be addressed soon. It took me a LONG time to determine my '94 Grand Am had a blown head gasket (I finally turned the car over to a good mechanic friend and at that point, not just did it have a blown head gasket, but because it was causing the cooling system to be over pressurized so many times, it blew the gasket on the side tank to the radiator, luckily a radiator under life time warranty). I changed the head gaskets myself in October of '09 on a '94 Grand Am with 180,000 on it. Today, I still drive that car (over 214,000) and it's running strong. But it's a gamble, I could have done all that work to have the car be a huge pile, but so far, so good.

 

As well as the car runs I will be surprised if my head gasket is bad but at the same time its hard to say where the bubbles would be coming from unless that night it was pushing out a big air bubble hense why I had no heat. Also seems to be excessive water coming out of my tail pipe as well imo.

I've gotten pretty good at bleeding my system so I think but that doesn't mean there's not a big air bubble plaguing me this whole time. I will get a compression check done to put my mind at ease. Either its good or not. If it is good I will go for my LIM gaskets. And if its bad at least I will know. I'm very mechanically inclined and feel I can do a head gasket. I just need to know if its bad.

 

If water comes out of your tailpipe, it's just condensation. If anti-freeze comes out of your tailpipe, that's a different story.

 

That was my thoughts when my head gaskets failed on the 3100 on my Grand Am (I was driving it for a couple of WEEKS, 40-80 miles a day trying to figure out why at least once a day my temp gauge would begin to go into the red and I've bled air out of the system like crazy). I did tons of stuff, bleed the system on the side of the road, replace the radiator cap (the Grand Am radiator system is a bit different as the radiator cap is the one on the overflow bottle, the real radiator does not have a cap).

I finally had a GM mechanic friend of mine look the car over and he put all the pieces to my puzzle together. He informed me the car runs REALLY well for a blown gasket (once it blows any coolant that collected in a cylinder out of the system, you would never know it had a problem it ran so good and it did not appear to have a true overheat and no weird noises). I've put about 35,000 miles on the Grand Am since changing the head gaskets.

I hope you get some answers soon, but so far it's lending itself to be a possible head gasket. FYI - THe mechanic that figured mine out did not do a compression test. Instead he hooked up a radiator pressure tester, ran the car to see how long it took to build up pressure, that with all my observations and attempted diagnostics is what pieced together the answer.

The 3100 is a tough little motor

 

No real repairs done yet just more updates. Drove the car this weekend to my gf's place about 45 mins each way. Before I left I added coolant and bled the hell out of it, ramped the engine rpm up a bit while doing so until I had next to no spitting coming out of the bleeder. Was a nice solid stream. The car sat for a bit before I got ready to leave(enough for the thermostat to close) Once on the road I immediately noticed the temp gauge looks to be reading quite a bit lower than it was before, and there isn't hardly a jump at all anymore when the thermostat opens.
Before you could watch and see the needle rise up to just under half way or so then drop down to "operating temp" and stay there once its open. This time around it rose up to a little above 1/4 and stayed there both on the way over and coming back(where it normally reads when its up to temp). Car sat at her place all weekend as we took her car out of town for the rest of the weekend.

Leaving this afternoon the car had no spots under it anymore so I am confident my external leak is finally taken care of so we can turn that page on that and focus on troubleshooting this suspected head gasket/LIM gasket. I will take the car to get a compression check done sometime early this week.

I also checked the oil fill cap and the brown gunk burned off through the drive there and back, which puts my mind a little more at ease that it was condensation and not coolant.

Were probably going to end up with a book of pages by the time all is said and done with this deal but I appreciate all the help so far!