2000 3.5L Coolant loss and misfire

[steffenk]

After fixing the coolant crossover pipe, I stopped a coolant drip. However, I've noticed that the car is still losing coolant (no drips). There is a gurgling sound. I had a misfire on #4 four mos ago (CEL blinking while driving) that I fixed by replacing a bad spark plug. Since these repairs, I have had a misfire in the mornings when I first start the cold engine - lasts 15-20 secs. Today, four months after replacing the plug, the misfire on #4 is back while driving (CEL flashing). Am I correct in assuming that this is a small headgasket leak that is allowing a small amt of coolant to get into #4? It seems that 1) a small amt of coolant fouls the plug in the morning until engine gets hot and 2) over a period of months the coolant kills the plug.
The engine temp is fine and there is no noticeable smoke from the exhaust. There is no obvious contamination of either the oil or coolant. Thoughts? And if this is a headgasket, any estimate on repair cost? Thanks.

[rhaigh08]

Can you smell coolant from outside the vehicle? The gurgling sound is actually quite common i'm guessing, both of my Intrigues 99 and 02 both gurgle not loudly but it's evident. When your head gasket goes it doesnt always necessarily mean oil will get into coolant and coolant will get into the oil. My sisters went on her grand am though hers was overheating there was no evidence or suspicions of it being a head gasket and it was. I have also noticed intermittent coolant usage on my 99 for quite some time about 2-3 yrs and nothing has ever come of it. Just about once or twice every 6 months I have to add about 2 quarts. Did you have any other codes? The CEL is flashing because there is a very serious issue with your car. My guess is that is a bad misfire meaning if you do not attend to it you may end up having to replace the quite costly catalytic converter. Believe me it happens quick if you dont get it fixed. However I find the CEL usually does not flash when there is only 1 misfire its always flashed at me for a random or multiple misfire. Before winter I did the 99s plugs just cheapy plugs. By spring I had to replace them again with the stock NGKS.

[carbon02]

Another way you might be able to verify coolant into the cylinder is to pick up the coolant system tester from Autoone. You need the coolant system tester, and the GM coolant bottle adapter. Pull the spark plug, pressurize the coolant system and keep it pressurized for a few hours. Then you can inspect either with a mirror and a light, or pull the ignition fuze so the motor doesn't start, and crank the engine. If coolant comes out the spark plug hole, you have a problem.

I read this, and thought it was a good idea.. I've stopped chasing the coolant leaks on the 2000 Intrigue, as it appears to have another bad PCS transmission issue. Car has been replaced with an Altima, but I just can't seem to have the heart to get rid of it, at least not yet..

[steffenk]

Thanks for the replies - much appreciated. I will work on confirming that it is a HG issue. If I do confirm this, any advice on whether the repair is worth it? The body is in great shape and the engine only has 70,000 miles. After repairing the coolant crossover pipe and putting new tires on it a few months ago, I would like to fix it and continue to use it. But, am I simply looking at many more costly repairs right after I repair the HG?

[steffenk]

Thanks. Agree it's a personal decision. For this one, I'd have it done - it's a reputable shop and they seem very decent. I do like the Intrigue and I've got a backup. The backup, a '93 Isuzu Rodeo with 197K, seems to be the one that never requires any work. The newer Intrigue is really the car I'm looking to be the reliable one. I'm leaning toward doing the repair but trying to build confidence that I'll come out of this with the Intrigue being a reliable primary car that I can count on.

[steffenk]

I've got my Intrigue in the shop, but they have not been able to come up with a conclusive diagnosis. They observe the same symptom as I do - misfire at cold start presumably because of coolant dripping into cylinder #4 overnight. They told me they pressurized the system for an extended period and don't see evidence of head gasket leak, i.e. white smoke from exhaust. They also told me there is no trace of oil in the coolant or coolant in the oil. They said they're leaning toward an intake manifold gasket and that the only way to tell for sure is to check by disassembling the top of the engine.

This just doesn't feel right . . . any input? I feel like if they tear into the intake manifold, the problem is not going to be there.