Discussed this with son-in-law Steve who owns an auto shop. First, the bad news. If it’s a V6, expect that a head gasket replacement will run $2,200 to $2,400. There’s aboiut 16 hours of labor to do this, with machining and all sorts of things involved.
But, some of these newer Pontiacs have a composition intake manifold, which frequently warps and causes coolant leaks. A shop can install this for around $900. And, if you’re game, the parts departments sell kits which include all the parts, and evidently it’s not a very difficult job for a DIY guy to handle. Good luck.
BTW, I don’t know about your dealer, but at Steve’s shop they would pressure test your car and tell you where the leak is for $43.50 plus tax. That’s a half hour labor, the minimum shop charge.
When I pick it up tomorrow morning I’ll give you all the itemized bill, just to pick over. Next time I’ll go to my awesome mechanic - I guess I panicked this time and then kept on a road I wasn’t comfortable with, etc. I still feel that regardless of the work done they did a horrible job of explaining what was going on and what my options were. (And of answering the phone, too.)
That’s a good sign. Once the anti-freeze mixes with it then it stay’s looking nasty. It may not froth up as much but it will change the look of the oil.
A head gasket leak can take on different characteristics depending on where it’s leaking. If it’s a really slow leak then it’s harder to diagnose but hopefully in your case it will be obvious (and not a head gasket).
Depending on the size and the location of the leak, you may not get visible smoke out of the tailpipe, or a sweet odor. (BTW GM cars have Dexcool, and I do not know if it smells sweet like Ethylene Glycol)
If the leak is not into the oil passages, the engine oil will not be discolored.
Now assuming that the coolant was full when the car was serviced two months ago, (and this may or may not be a fair assumption I didn’t do the service) Two months is a slow leak. That is not a gusher.
There is also one additional possibility that has not been discussed. It could be the engine overheated, and kicked a bunch of coolant out of the pressure cap, and there really isn’t a leak, but there might be a failure of an electric fan or other part of the cooling system.
This would explain why the car got warm in at a stop light and cooled down when the car was driven, the ram air cooled it off.
I am/was the proud owner of 3 GM V6’s. I have had to fix 3 coolant leaks due to intake manifold gaskets. Two were pretty severe, one was a small constant trickle.
I used Block Seal. I have had no more problems.
Someone might come along and tell you it’s not a permanent fix. However, the Pontiac Grand Prix with 220,000 miles is still trucking along. The Buick Regal with over 200,000 miles is still rolling around town. And we still see the Lumina driving around.
Granted, we don’t own the Buick or the Lumina (we sold the Lumina for $750 and gave the Buick away) but I seriously doubt the new owners put $1200 into them.
This is what I would try first. Block Seal, made specifically for this application and it works.
GM V6’s are NOTORIOUS for intake manifold gasket leaks. Now this only works for coolant leaks, not oil leaks. Cost you $20 and four hours of standing around, draining and filling the radiator or go for the $30 can which will work with residual antifreeze in the radiator.
Well, if they did do either of those tests, they magnanimously didn’t charge me for them. The two things on my receipt:
Cooling System: Low Coolant Light Comes On - Advise
Flush cooling system out and replaced thermostat
The parts are coolant, thermostat, and rad flush, plus labor - 202.44.
Front and rear brakes: Brake light came on this morning and went back off - Advise
Replaced front and rear brake linings. Resurfaced brake drums and rotors as necessary
Two pad kids plus labor, 401.89.
Shop supplies, etc.
Grr. Why not just tell me you weren’t doing the tests I asked for? I feel stupid for not taking it to my mechanic, but it was all the way across town (with no coolant) and I had to get to work and… crap. I’ll probably be right back there when it happens again.
Yeah, this is one of those places where “roadside assistance” comes in handy. I get free towing for 3 miles, and then I pay some ludicrously small rate for each additional mile, like 3 dollars or something. So next time, you know to have the car towed if necessary to a garage that you trust.
I’m sure it was just a mis-type, but the head gasket is located b/t the cylinders and the cylinder heads. Someone may have already corrected that , but i didn’t see it.
The first sentence of that wiki article is wrong (or incomplete at best). Between the cylinder head and the engine block, one finds the cylinders (and 2 gaskets). There is a head gasket, located at the top (or head) of the cylinder and a base gasket, located at the bottom (or base) of the cylinder. But I digress. I did not mean to hijack, just wanted to point out that error. My anal-ness is not relevant to her problem.
I think you must be assuming wet liners.
No engine I have ever taken to pieces has had any form of gasket at the lower extremity of the cylinders, they are open ti the crankcase and completely unsealed other than by the piston/rings.
I have had a few Renaults with cylinders with wet liners but have never dismantled such an engine. There was IIRC a seal at the bottom to prevent the water jacket leaking into the crankcase but otherwise - no!
There’s nothing wrong with that sentence. The majority of internal combustion engines are in cars, and the vast majority of them have engine blocks.
Now, on most motorcycles, the cylinders are separate piece from the crankcase, but neither of these parts is called a block. Some of them do have a cylinder base gasket between the cylinders and the crankcase.
Are you sure the electric cooling fan is coming on? if not the car would overheat while stopped and the coolant could be lost though the overflow in the expansion bottle. Or maybe not it’s been a long time since i have under the hood of a car.
With the exception of air cooled VW motors and maybe Subaru motors, the Wiki article is 100% correct. Even with a wet sleeve motor, there is an engine block around the outside of the liners.
Look at the picture in the Wiki article. It shows the engine block and head gasket.
there was nothing wrong with what ECG wrote.