I've had my Monte Carlo 2001 since March this year. When I purchased this car it had 126,000 miles on it. It never really blew heat and the low coolant light would occasionally come on then off. Now with 155,000 miles the car is running hot and screams high coolant level but when I pop the hood, it doesn't seem hot but I do hear bubbling. I've had a radiator flush, which gave me nice warm heat for about a day. So, I took it back to the mechanic and he said thermostat, replaced the thermostat, car still running hot Now the mechanic is saying head gaskets, SAY IT AINT SO! I was wondering if they did a pressure test on it and is that a common service when diagnosing this problem? I read that the head gaskets don't blow often on the Monte 01 and it could be the plastic elbows that connect the intake and water pump to the tensioner pulley bracket, whatever that is?!?! My exhaust isn't blowing white smoke & my oil dipstick looks like it should. HAS ANYONE ELSE EXPERIENCED THIS PROBLEM WITH THEIR MONTE CARLO? Im really depending on this car for at least 50,000 more miles. WHAT SHOULD I DO?

 

Could be the elbows...(common issue) also upper and lower intake gaskets are a common issue.

Im sure someone else will chime in with more answers or solutions...

 

First, which engine is in your Monte (I did not see that or the trim level of SS). The coolant elbows are a 3800 engine ONLY item and usually when those have problems you are loosing coolant.
As for the heater not blowing warm, first two steps should have been a coolant flush and change the T-stat (as the T-stat may be sticking open).
The 3100/3400/3800 engines are known for intake gasket failures. The gaskets are nylon and last 80,000-120,000 miles on average, at that point, they fail. Failure symptoms may include loose of coolant, lose of oil and signs of coolant mixing with the oil. Renting a radiator pressure tester from a parts store can help tell you if the intake gaskets are bad (get it to the appropriate pressure, then look and listen for hissing and coolant bubbling from a gasket matting surface).

As for your temp issues, my first point of concern is has all the air been properly bled out of the system. A small air pocket can cause the temp gauge to read high when there is no real problem. If there is an air pocket, that needs addressed before going forward.

As for head gaskets, I have had issues of bad head gaskets causing air pockets in the cooling system. The white smoke, at least on some modern cars, is a result of prolonged head gasket failure.

I hope this helps some. Let us know what engine you have and we can help pinpoint a little more info.

 

Hi The_Maniac I've been waiting for you to reply *wink* lol. When I popped the hood the engine reads "3400 SFI" I had air pockets removed first and a radiator flush and the car blew heat for about a day then started running hot again the temp gauge would go all the way to the top and the car would scream "high coolant temperature" but when I pop the hood it doesn't seem hot. I do hear bubbling though. The thermostat has been replaced and its still running hot and now only cool air blows when the heat is on. The mechanic is saying head gaskets $1100 repair and recommended that I just get a new engine

 

First, you have a 3400, so coolant elbows are not a factor here (as you don't have them).
Second, I hate to say it, I think I may agree with your mechanic. it sounds like you *could* have early stages of head gasket problems. If it is the case, here's what you have going on:
- As the car runs, 1 or more cylinders is forcing compression gases into your cooling system via a crack in the head gasket.
- The compression gases are forming a new air pocket, this results in the temp gauge going high, and explains why the engine is still cool to the touch (the compression gas formed air pocket, when it sits on your temp sensor is read differently then hot fluid).
- The bubbling you hear is the gases finding an escape.

Now.... With prolonged driving, the car's cooling system will only handle so much of this. The cooling system is designed for a max of 13-15lbs of pressure (when pressure exceeds this, the radiator cap will allow the over pressure to release into the coolant overflow bottle). But those compression gases could eventually cause higher pressure levels then the system was designed to take, and basically the pressure will damage the next weakest link.

I went through this on my '94 Grand Am a few years ago (it had the 3100, same block and basic design as the 3400). The symptoms began for me as a small rough idle from cold start for about 30 seconds (this was due to coolant that leaked into the cylinder over night). Then the weird, unexplained over heat (heck, I used a radiator pressure tester and everything was showing good, the car held pressure just fine). Eventually I had to pull help in on this diagnostic and by that time the over amount of pressure blew the gasket to the side tank of my radiator (luckily, the radiator was a life time warranty item).
I did the head gaskets my self. While I did that, I also:
- had to replace an almost failed motor mount
- replaced factory original heater hoses
- replaced the LIM gaskets
- replaced the radiator (under warranty)
- replaced spark plugs
- Degreased the heads, rockets and push rods (almost clean enough to eat off of)
I did NOT send my heads to a machine shop (but it is recommended). The shop book documents checking the decking surface of the heads with a straight edge for signs of warping (mine passed). With all I did, using FelPro gaskets, parts, fluids, I spent about $330.

Sadly, when I did mine, I did not know FelPro now sells an aluminum LIM gasket (highly recommended, all plastic/nylon LIM gaskets are 100% junk and it's maybe $20 more for the better gasket).

Now, I did the head gaskets on my '94 Grand Am back in October of 2009, the car had a 180,000 miles on it. I just sold it in perfect running condition this October (3 years later) with 215,000 miles on it. The 3100/3400/3800 v6 engines are very good engines so long as they are properly maintained.

I'm curious why your mechanic recommends a new engine. Any salvage engine you buy, I would encourage if you're keeping the car for the "long haul" anything over 100,000 miles, replace the head gaskets for piece of mind (or at LEAST the LIM gaskets, they fail about 80,000-120,000 miles on average with the crappy nylon gaskets). $1100 to replace the head gaskets (and I would assume using FelPro aluminum LIM gaskets) is not a bad price for the work of a shop to do. That job can be at least a full Saturday job if all goes well (like no bolts snap off) and the person is experienced with the job (otherwise, assume a weekend). So, it does involve a lot of man hours to do. I worked on mine outside and it was mostly a couple hours here and there (plus, I did not order ANY parts until I got the heads off and verified they were not messed up).

Sorry for the mile long post, but I hope it gives you a lot of good information.

 

yep that's exactly what's doing sorry to hear but just wanted a second opinion thanks The_Maniac you were of great help!

 

I'm not trying to play devil's advocate, but I tend to agree with your mechanic's suggestion. If you were told the head gaskets needed attention the first time you took it to the mechanic that means (on the pretense proper testing was done) leakage was detected. Damage has already occurred, and will continue to occur as long as the engine is in use. If any water at all has made it's way into the crankcase there is the possibility of bearing damage. Overheating can create hot spots that will distort surfaces and cause excessive wear to internal parts. It's a crap shot the bottom end of your engine will survive with a fresh top end. To charge someone $1100 to do the top end knowing it could set them up for bigger headaches in the future would be of concern to me if I was diagnosing your vehicle. For the money (and peace of mind) I think I would also recommend a new long block or (depending on shop policy) a low mileage used engine. Of course, you could get lucky. You might slap a set of heads on it and drive it for years to come. It just depends on the severely of damage. How often the engine overheated, the load on it, ambient temperature, etc. all factor in. That's the crap shot. Good luck with whatever you decide.

 

You certainly bring forth some good information and sadly, it's hard to judge without inspecting the car personally.

What I will say does not mean it's the rule (they can be the exception). In the case of my Grand Am, the smaller, harder to pin-point symptoms began about a year before changing the head gaskets. I got fed up one night trying to wrestle out what the problem was I had to contact my "GM Guru" (a master mechanic who I bring in on my big mysteries). He was the one that gave me closure to diagnosis and I could begin the repair. He admitted, in my case for having a blown head gasket, once any coolant in the cylinder blew out, the car ran exceptionally good. Also, my oil change intervals of every 3000-5000 miles may have played some factor into that.
I also know other 3100/3400 engines belonging to friends of mine that had head gasket failures diagnosis a LOT faster then mine and no issues after replacing the gaskets.

But, you are right in saying, it's tough to be sure what's going on in the bottom end. I know when doing this job, my friends and I typically degrease as much as we can of the components. Also, before starting the car, ensure a fresh oil/filter change. Drive it about 500 miles, change the oil and filter again (effort to try and remove as many contaminants as possible). So far, these practices have ended in good results. Odds are, most mechanic shops don't put that TLC into the job, this could impact the longevity of the engine after the job.

I'm by and far NOT a seasoned mechanic, just a guy that turns a wrench on his own rides (and helps others when he can). A seasoned mechanic has more field experience to judge this differently then I.

Again, the success stories I know may or may not be typical.

I guess the bottom line is, you need to work with a mechanic you TRUST otherwise you would not be seeking our input. I've told others before, if you don't do your own wrench work and you rely 90% or more on a mechanic for diagnosis and repair, find one you trust as much as you would your primary doctor.

 

hmmm...O3ssle I understand what your saying but I don't have a regular mechanic. Until recently I've driven newer cars that mostly needed new tires & oil changes but I do love this Monte that's why I'm really trying to research what's what with it so I can keep it. Doesn't seem like I can afford to maintain it though, not right now anyways ): I was trying to save myself some cash by paying $4000 for it in March, didn't turn out to be a good investment ):

 

I've bought a bunch of used cars without warranties and for the most part, been pretty lucky. My '02 Grand Am I have came with a lot of low cost surprises (but I've luckily turned it around from a bit of a basket case back to almost 100% normal good car).

As for your Monte, if you have any doubts about the the opinions of this mechanic, find out a mechanic your friends/family/co-workers trust. Sometimes a good referal is worth it.

Since I'm a little handy with a wrench, I'd change the head gaskets myself BUT then again, I'd also be able to inspect it personally and have a better idea if it's worth doing or not based on sounds and behavior of the car.

You can also get a second opinion (but I would not tell the second person what the first guy told you, let them do an independent evaluation).

Best of luck man. Trust me, I understand the pain. My first car ('84 Buick Century with a 4-cylinder), I knew NOTHING about car repair, and it too ran into a blown head gasket problem. Luckily my father was very handy and helped a lot. But it was still a crappy situation.