When the car is in motion it starts to overheat?

Hi,

Was it overheating prior to replacing the thermostat? I ask because you may have gotten air into the system which is causing a blockage. Don't laugh, but does the heater work?

On the other hand, this could be related to a faulty head gasket. Take a look through this link and let me know if anything mirrors what you are experiencing.

https://www.2carpros.com/articles/recognizing-the-symptoms-understanding-a-blown-head-gasket-in-your-vehicle

Also, take a look through this link. It explains what to look for.

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

Let me know your thoughts.

Take care,

Joe

Thank you, Joe, for replying to me so quickly... There are bubbles in the coolant when I take off the radiator cap, but is that a definite blown head gasket?

Hi,

If the bubbles are constant, chances are there is compressed air from the combustion chamber making its way into the cooling system.

When you say bubbles, do they look like the ones in the link I sent? If they do, you should do a chemical test to see if there are exhaust fumes present. (See step 4 in the "Head Gasket Blown Test" above)

Let me know if you are comfortable performing that test. Also, if you could get a few pics of what you are seeing, it may help.

Let me know.

joe

Hello Joe,

The bubbles are like the ones you would see in a pan of simmering water on the stove. In between a simmer and a boil.

Hi,

If that is happening when the engine is cold or warm, we need to do the chemical test in the link above. It shouldn't be doing that. I suspect we have a head gasket issue.

Let me know if you are able to do the test.

Joe