The car is a 2000 Camaro with a 408 stroker A4. So the other day i took the car to a car show and noticed on the way back that it was overheating and almost in the red. I didn't think nothing of it because after a min or two it cooled off. But 2 days ago I took it to get it inspected which was about a 35mile drive about half way there I noticed that it was once again over heating but this time it wanted to stall at every light or stop sign. At one point it stalled at a stop sign and struggled to turn on and when it did the rpm gauge didn't work but then started to work again. But the weird part is its only over heating when I coast down a hill or up one. When I'm driving or idling its fine runs where it should. I checked and the fans are running and all of my air deflectors are there. Does anyone have any idea or have has similar issues?

 

Check all your connections and replace the temp sender

 

thank you i will try that out. When I look at it with a heat gun it does show roughly the same temp. But why would it stall and act funny at the same time as the car overheating. If it matters its a speed density tune with the o2 sensors off if that helps.

 

I suspect air in system. Cooling system configured as factory original?

 

I have a stock gm style water pump. I also have an aluminium radiator I think dual core or something like that and also stock ls1 fans I believe the thermostate is stock temp as well.

 

do a 160 thermostat and see how that works out. My engine runs cool as a fall breeze even in the hot summers in AZ.

 

I thought the higher the temp thermostate the cooler the engine because it keeps the antifreeze in the radiator longer or am I wrong i think I have a 180 in it now

 

Your symptoms match a failing (sticking) thermostat.

If you've tuned the PCM for different warm up enrichment and timing adjustments, lowering the thermostat temp will help keep it cooler. If you don't adjust the PCM calibrations for the lower coolant temperatures, you PCM will still try to run the engine rich and adjust timing for more heat, less power up to the "factory" thermostat temperature, and you'll see better performance with the factory thermostat temperature.

 

The speed of the coolant is about the same when the thermostat opens. Between 160 and 180, the 180 thermostat will keep coolant flow through the radiator near zero, so that's a lot slower, but the radiator also cools less coolant (none) when the thermostat is closed. From 180 to 190 ish, the 180 thermostat will be partially opened and the 160 will be fully opened. Above 195, both will flow about the same.

Heat transfer is increased slightly when the temperature difference between the coolant and the ambient air is greater. So you do see slightly more cooling in the radiator with a 180 thermostat (or a 195 thermostat) than with a 160 thermostat. The difference isn't very significant, though.

 

The thermostat only regulates minimum temperature and will do nothing to solve an overheating issue.

 

Captan Obvious says, if the "overheating issue" is caused by the thermostat sticking closed, replacing it with any working thermostat will solve that issue.

 

Perfectly explained 😂🤘🏽

 

Obvious if that was the issue but it's doubtful that it is considering it only overheats on hills as the OP stated, A stuck thermostat would not cause that issue, If stuck closed then it would overheat almost immediately and one stuck partially open would cause it to overheat with a load and stuck fully open it would run cool at times at normal at others.

By the way my comment didn't have anything to do with a stuck thermostat, 02*C5 stated that he ran a 160* and suggested running a cooler thermostat might fix the issue when that is also not correct.........Unless the current thermostat was bad and if that was the case like you said any thermostat would fix the issue.

Captain Obvious....Out!

 

I'll take a pick the next time I'm out in the car so you can see where my temp runs. It's rums cool all the time. Even when it's 110* ambient temperature which puts the road temperature radiating back into the car we'll into the 120*s+.

 

That actually means your cooling system is in very good shape. The electric cooling fans do a better job than engine driven ones as long as the ECM turns them on when they are supposed to. My 200k mile Tahoe with its engine driven fan does decently with an OEM 187 degree thermostat. Only long idling with the A/C on moves the needle up. Electric fans coming soon....