As title states, my cavaliers coolant temp rises a bit over half in standstill traffic but once it’s moving 10-15+ mph then the coolant temp significantly drops to a little under half, I’ve tried turning my car off when it’s doing this to help cool it down and the radiator fan stays on for a while after turning the engine off when the coolant temp is this high, what should I do?


My coolant isn’t dirty looking, and I haven’t had to add coolant in 20,000 miles now, it’s still at the max line, so no leaks or burning.


is this normal? I was told cavaliers cooling system is based on movement.

 

Welcome from Florida. You could have a bad themostat.

 

You cooling fan probably isn't coming on. There could be a number of causes for this, but pluck the low hanging fruit first: fuses, relays and look for wiring and connector faults on the fan and temp sensor.

 

1. turn on your heater and turn the fan up. The heater works using coolant from the engine, using the heater pulls heat from the coolant and cools the engine.
2. Take your thermostat out, you don't need it. I removed mine 10 years ago. If you leave it in and it sticks closed and the driver isn't watching the temp, you get to replace the head gasket 'cause it will blow.
3. Do a radiator flush.
4. What your gauge is showing in the photo isn't an overheating situation, it's just running a bit hotter than normal. Mine does the same thing.

 

Do not remove your thermostat. The engine won't run at operating temp, you'll be burning tons of fuel and have various other problems.

 

Negative, Ghost Rider. My Cav runs at the same temp without the thermo and mileage is also what is should be. (Actually my mileage is a bit better than book value because I'm a hyper-miler.)
Those living in cold places should probably leave it in, but for warmer places it's not necessary.
A sticking thermo can blow a head gasket very quickly if the driver isn't attentive. With no thermo, there are no such worries. IMHO

 

Bull. This takes away the vehicle's ability to regulate temperature. It will take longer to warm up, run in open loop longer, and overcool on the highway. Engine oil will build up contamination reducing the life of your engine.
It's going to run rich and destroy your expensive cat quicker too.

Don't listen to bad internet advice. Ask a professional mechanic.

I've never had a thermostat stick closed, but you'll know if it does.

 

Yes, I've heard all the scare stories, none of which have come to pass. Pulled the thermo out of my wife's '99 Ford Taurus when it stuck a few years ago also, no change in operating temps.Thankfully, I was driving it when it happened, so no damage.
Again, cold-climate cars, sure, warm climate, no need.
My Cav is an '02 model (bought used from Hertz), so it's only 21 years old now (and still burns zero oil), but maybe in another decade or two the engine will suffer damage from running without a thermo.
I've been wrenching on and writing about engines (for manufacturers) for many years so I do have some experience in these matters......

 

... yet. Or you ignore it. Or you've just been lucky. I guarantee your fuel economy is worse than it could be.

If you didn't need a thermostat, it wouldn't be there.

 

if you want to do this yourself that is ok. Do not tell other people to do this. Cold running engines create sludge in the oil as water from combustion will not evaporate off easily. The engine will run rich and burn more fuel.