I’d also note the heater is no longer working…

 

do the hoses get hot and feel pretty firm when up to temp?, you may have two separate issues.....leak and bad temp sensor, what does your dash and scan tool say? you could also still have lots of air inside the system

 

The computer doesn’t spit out anything, the dash doesn’t display anything until the obvious overheating issue: “engine overheated A/C off”. I’ve tried scanning it for codes several times with no results. As for the hoses, they feel firm but not exactly warm.

 

No heat in the cabin and overheat messages sounds like an air pocket in the cooling system somewhere.
These cars can be very tricky when it comes to coolant exchanges and replacement of system components.

 

Thanks for the reply- I received the same diagnosis from a reliable source today. I ordered a coolant burping kit to get all of the air out, so I'll revisit this thread once it comes in. Is there anything I should know or do prior to/during the burping process?

 

The Air-Lift has always done right by me. Putting the entire system under vacuum ensured the coolant is drawn throughout the system when filling.

 

Thanks, I'm going to try the cheaper burping method first; if it continues to overheat and symptoms still point towards air pockets, I'll buy a kit. Can you provide a link for a good brand to use on this?

 

Just an update and to close this one out, my problem was in fact air pockets in the system (thanks @Long !). Took a good 45 minutes to fully get all of the bubbles out, but overheating issues went away, heat came back on, and coolant level is stagnant. For anyone else experiencing this problem, I only needed the kit below and a few quarts of coolant (I bought 2 gallons to be on the safe side).

Amazon.com

http://goto.walmart.com/c/404739/56...BhAOEiwAj4gpOZa7rnAQWnYRNX4BevIk4eGlTCCIco-nEK-l0ljS9TxTvj8JDEprdxoCkk0QAvD_BwE

 

Happy to hear your overheating issues are over.
Well done.

 

Hello friend, I am by no means a certified mechanic, but I try my best to tackle on a mechanical issue before I throw in the towel and take it to the mechanic and see my money fly out of my hand. I had the same problem about the car overheating. I replaced the radiator, radiator fans and water pump, I flushed the system out. I even changed out the thermostat and it was still overheating. Finally, I decided to take the thermostat out and leave it out and guess what??? I don't have an overheating problem anymore. Houston, My Cadillac CTS has lift off meaning NO MORE PROBLEMS!!! I hope this helps anyone out.

 

I would strongly discourage running your vehicle without a thermostat and I'm willing to bet your removal of the 'stat was merely coincidental with the end of your overheating issues which likely persisted due to air pockets remaining in the cooling system.

 

I would strongly discourage running your vehicle without a thermostat and I'm willing to bet your removal of the 'stat was merely coincidental with the end of your overheating issues which likely persisted due to air pockets remaining in the cooling system.

Well, It's been close to a year and I still haven't had an issue with the Caddy overheating, but I guess I was just lucky. Here in Texas we really don't have bad winters in Houston and since the thermostat usually regulates and adjusts the water flow for the heat, there is really no use to have a thermostat. Again, I don't claim to be a mechanic, but I've been working on cars/trucks for over 40 years.

 

The thermostat has very llttle to do with controlling water flow within the block circuit. It controls flow to/from the radiator in order to maintain engine and system temperatures within a design operating range, usually about 185 - 210 degrees F for most efficient engine and systems operation and fuel economy. Operating without a 'stat is harmful to the engine and leads to shortened oil life as well as internal parts wear. Regardless of whether you're in Houston, Fairbanks, Murmansk, Miami, or Saudi Arabiia.

 

It's clear you aren't a mechanic. Your engine will thank you if you put your thermostat back in, and will last longer as well.

 

Yeah, I said from the beginning that I wasn't a certified mechanic but I'm not having overheating issues anymore. Try to be nice and not try to upset people that you don't know. We are here to help each other out.

 

In cooler weather, recent GM vehicles will also shut off the A/C, zero the coolant temp gauge, and set a warning when the thermostat is removed or stuck open because the ECM expects normal operating temperature to be achieved in a fairly short amount of time and this is thermostat controlled. When the expected temperature isn't read, the ECM takes steps to protect against an overheat condition because it assumes the coolant temperature isn't working properly so the engine temp is considered unknown.

This happens frequently because someone decides to "improve" their car performance by removing the thermostat or putting in one with a much lower set point than stock.

Becuase your CTS hasn't set a warning in over a year of operation, I would suspect that there is still a cooling system issue and removing the thermostat was sufficient to let it avoid overheating but these problems tend to get worse so expect whatever the underlying cause is will make its self apparent again.

Rodger