Engine is overheating?

The coolant reservoir is on the left(drivers) side of the engine compartment, between the left strut tower and the firewall. I have yet to see one of these overheat, what were the conditions under which it happened? If you had lost coolant, it should have given a check coolant message. Where there any warning signs other that it going to idle? This guide can help us fix it

https://www.2carpros.com/articles/engine-overheating-or-running-hot

Please run down this guide and report back.

No warning at all. A/C was off . This happen in Riverside Ca weather 93 degrees

What did the gauge read? How did you determine it was an overheat?

No warning at all. A/C was off . This happen in Riverside Ca weather 93 degreesNo warning at all. A/C was off . This happen in Riverside Ca weather 93 degrees

The gauge shot up less than 45 seconds . Then the car read.overheating and went into idle to protect it

Something so sudden like that, I would be suspicious first of all, that it was truly overheating, and not just something falsely registering. If the coolant level is full, check the belt(although if it failed you would have lost power steering). The thermostat is on the rear of this engine, a real bear to get to. That would be another place to check.

I do see a little leak

Another thing to consider, is the vehicle still should have powertrain warranty to 100k. Your owners manual will shed some light on what is defined as 'powertrain', but it may be warrantible. On the earlier 3.6, the water pump was known to leak, I don't know as though the pump changed on a 2008.

Thanks for all ur help going to have it towed to the dealer

Hi Maurice12,
I know it was a long time ago when this issue happened to your CTS, but my 2008 3.6L DI CTS4 just had the exact same sudden over heating occur, and their is a slight leak of clear water looking liquid. I was just wondering if you remember what the dealer found out was wrong?

My cts overheated today and all the bells started going off saying overheated , engine lost power went into idle. The past few days I've noticed that the fan was running after I cut the engine off for a while. It evinrually would shut off. I had been keepin an eye in the temp and it was staying right at 220. However it shot up to the max when all this happened. Any idea what's going on with it? Could it just be low on water?

It's either low on coolant or the water pumps not pumping. Check and fill the coolant then run the car and turn on the heater. If the car gets hot but the heat doesn't, then the water pumps not moving the coolant and needs replaced

My Caddy CTS with 3.2 engine just recently over heated. I am the original owner and have had very good luck with the car. When it overheated the antifreeze turned into this brown sludge like liquid. I feared that maybe the head gasket blew. I drained the engine oil and founf no antifreeze in the oil. There are no leaks that I can see from above or below. Is this an issue with the thermostat failing or is there a more serious problem?

Was it low on coolant, or overfull. The sludge like fluid is a concern, you need to check the trans fluid, the cooler in the radiator could be leaking, and if the trans fluid is worn, it could be brown. Also, the engine oil cooler is in the valley of the 3.2l, it could be leaking as well. You should not have anything oily in the surge tank, unless it was added by accident. The fact that there is no coolant in the oil, can be two things, the oil pressure is greater in both the trans cooler, and oil cooler, or the amount of coolant that leaks the other direction is small enough that it is boiled out and released as steam. Is there any sign of moisture on the oil filler cap(milky substance)?

It's the intake manifold gasket

If it was a blown head gasket there would be coolant in the oil. I had oil in the radiator but no coolant in the oil.

"If it was a blown head gasket there would be coolant in the oil."

That is not correct. When a head gasket leaks, coolant in the engine oil is by far the least likely outcome. More than 99 percent of the time coolant will be dawn into a cylinder, burned, and will show up as white smoke from the tail pipe. You'll be adding coolant on a regular basis, but it won't change color.

No transmission fluid, and to my knowledge, no engine oil flows through the intake manifold. If oil does, it is only related to drain back passages where that oil is not under pressure. Oil under no pressure won't sneak into coolant under 15 pounds of pressure.

My vote is for Factoryjack's comment about the transmission cooler in the radiator, especially since this is a GM vehicle. GM uses the red Dex-Cool antifreeze and they advertised it as "lifetime" coolant to make their cost of maintenance appear to be lower than that of their competitors, then they put a sticker under the hood saying to replace it every three years. Even the Dex-Cool company doesn't recommend waiting three years. Water pump lubricant, corrosion inhibitors, and other additives wear out in about two years, then the coolant becomes acidic and attacks metal parts. That's why we need to replace it. GM owners are all too familiar with leaking heater cores and radiators due to this Dex-Cool. A lot of mechanics won't put it back in their customers cars. There are alternatives that meet the same requirements for these engines. You can't mix in other brands of antifreeze either as it turns to what we call, "Dex-Mud". That is what happens too when transmission fluid mixes in. You will likely find the transmission fluid has turned pink or light brown.

To test to see if the coolant has turned acidic, use a digital voltmeter set to the 20-volt scale. Put the negative probe on the battery's negative post or a paint-free point on the engine. If you have a radiator cap, remove it, then stick the positive probe into the coolant, but not far enough to touch anything metal. The engineers forgot to put radiator caps on most of their radiators, so you'll have to go to the reservoir. Any reading over 2.0 volts is excessive. It's not uncommon to find 4.0 to 6.0 volts. By the time it gets that high, it won't be long before the heater core is leaking. Often that leak is blocked by residual casting sand from the engine settling in the heater core. When the cooling system is flushed, that sand is washed out, then the leak becomes apparent and the mechanic gets the undeserved blame for causing the leak.

so my car over heated a little tonight.. it told me it was low on coolant.. i checked the coolant resovor if was full?.... what could it be?

Several things can cause an engine to heat-up. If the coolant is full, make sure the cooling fans are working, check the thermostat, and make sure none of the hoses are collapsed. Let me know what you find.

the fluid level switch in the jug needs replaced.did the dic say the car was overheating? what was the temp.?

I just purchased this car less than one month ago from a used car dealership. The check coolant lever light kept coming on. Finally five days after I bought it, it started overheating. I took it back to them and they said they took the thing that holds the coolant out and put in one from another 2006 CTS they had on the lot (they also said they did the same thing with the radiator and the lines, I know that was a lie) the car did stop overheating so I thought everything was fine. Then two weeks later after it snowed I noticed a huge puddle of coolant under my car, the light has not come back on but now the car is shaking while in park and while driving at a low rate of speed. So much to the point that I turned it off because it felt like it was going to go out. The check engine light came on the night I bought it and the oil said it had 12% life left, now it says 0% is that possible within a month if there is nothing else wrong? Please help I know next to nothing about cars.

Good morning,

First, you need to have the code read for the check engine light. A parts store will do it for free for you. Once I know that I can further help you with that.

https://www.2carpros.com/articles/checking-a-service-engine-soon-or-check-engine-light-on-or-flashing

As far as the overheating, you need to have someone pressure test the system to see why the coolant is leaking. Hopefully, it is something easy but needs to be tested.

https://www.2carpros.com/articles/engine-overheating-or-running-hot



I am concerned that it may be a failed head gasket from overheating.

https://www.2carpros.com/articles/head-gasket-blown-test

Roy

when i turn my A/C on the overheat light comes on. i see no leaks.

Check that the fans are coming on with the A/c and also get the radiator core cleaned start here. This guide should help.

https://www.2carpros.com/articles/engine-overheating-or-running-hot

Please run down this guide and report back.