telly444

took my Z on a road trip and the weather was a bit cold, just above 0 in the morning . so as I'm driving my temp won't go up past 155-160 sometime dips to 150 on the gauge. now what happened is my temp gauge went to zero my HUD went 100% on the coolant temp, and my screen in my dash said xxx temperature, engine running hot, A/C disabled. this tripped me right out. car is running cold, coolant is fine, but computer is telling the car is over heating? I unhooked the battery and it went away for now, but my temp still stays pretty low( 150-160) which makes the ecm go mad. lol maybe I should switch to a 180 T stat because of the cooler temps in Canada? I have H/C and supercharged 07 Z so I thought cooler thermostat would help. any thoughts, ideas, or comments? could my T stat be stuck open? could my tuner fix this by changing fan speed? change to 180?

dentalfloss

It may have nothing to do with your stat. The C6 does not like cold weather. Others have had these problems. Do a search on it.

vertC6

I would, your thermostat is opening at 160 then cooling off the motor. I would switch back, optimal temperature is 200-210

schpenxel

Agreed.. I'd at least get it back to 180. 160 is too cold, especially in cold weather

Corvettinator

Great example of what a thermostat is for. It's to warm up an engine, not remove heat.

6Speeder

YOUR 160 thermostat is bad, it's probably not closing. It is also causing the other symptoms you described. With a WORKING 160, even in cold weather my car cruises at 170. In hot weather it's more like 180.

The 160 is the best choice for performance, you just got a bad one. Over 200 degrees ECT is best for emissions, that's why GM set the Vette up as they did, but 180ish will make more power.

vertC6

No I think the 160 is doing exactly what it is supposed to do. When it opens at 160 that ice cold radiator water flows into the motor and keeps it cold, right around 150ish. The 180 is going to keep the engine at the temp it needs to be. It's way to cold in Canada for a 160. Any tuner/engine builder will tell you 210 is about perfect for engine temp.

Bill Dearborn

The stock thermostat is 86 deg C (186 deg F). Go back to stock. However, your weird symptoms where you are getting indications the car is overheating may be due to something else.

Bill

Dano523

Ditto, a lower opening point T-stat is not going to allow more water flow through it, so it just becomes the point of what the T stat opens at instead.

The car wants to run in the 190 to 215 range, and when you use a lower t Stat with nothing else changed ( read no better cooling radiator), then its the fan "turn-on" temp point that you have to lower to bring the fan on line in to try to drive the temp back down than what the system wanted to run in the first place.

The glitch, the fan connector at the side of the radiator is the weak link in the system, and when the stock fan is pushed to hard/for too long to try to keep the temp down, it ends up melting the connector.

Also to point out, it's possible to freeze shock the engine, with too low of temperature Dexcool, making it's way back to the hot block.

dennis50nj

it cleared because you disconected battery or you can clear the codes if you use a reader, what is happening is you need to reach 167 degrees in a certain time frame or cycle, if you dont the problems will come, i idle until i reach 167 and no problems , and when colder temps in the winter and cant reach the 167 driving down the road after a warm up idle and the temp drops into the 150s driving but goes up when stopped, i slip a piece of cardboard in front of the radiator from underneath the front, and it works fine for winter and take out in warm temps, heated seats are a must

blkbrd69

Your tuner can fix it. Has happened on both my C6"s when I went to a 160* stat before the tune. And thats in Florida winter?
Car thinks it has a problem and goes into protective mode as it does not reach temp. in time.
If I was in Canada I would run the stock thermostat, if anything so the heater works well.

timd38

Make sure you don't have air in the system.

Rebel 1

100%
I have a SLP 160 stat in my car and it runs 172-180 degrees which as right where i want it.

6Speeder

A thermostat is NOT like a light switch, all on or all off. The stock thermostat just STARTS to open at 186, there's very little flow till almost 200 degrees. Check it in a pan of water as you heat it up. You'll see. Same with the 160, that's why it keeps cruise temps at 180ish.

The ECM starts to pull timing (hence power) when the ECT gets into the mid 190's (depending on the model/year) so keeping your ECT just a bit cooler than that will ensure max power and stave off detonation.

The weird symptoms are from the ECM reacting to the low running temps from the bad thermostat. Why they (GM engineers) have the car show overheat when it's actually too cold is beyond me, but that's what they did.

telly444

It runs great in the city 180-190. its on the highway that makes it go retarded 155-160, gonna change to a 180, I'm sure that will be good enough.

telly444

at 9 degrees C on the highway, I doubt it will run at 180.

Rebel 1

It runs Exactly what i stated whether it's 32 degrees F. or 100 degrees F. outside. Makes no difference.

AORoads

Can't tell you which brand it was but I thought I read years ago that some branded/vendor colder thermostats were defective. Don't know if a search will turn it up, but it might. I have read of others tho that have had similar issues; just can't recall if theirs were due to defective thermo.

6Speeder

A 160 is the better choice, it's just that you got a bad one. Take it out, it's probably open partially at room temps.

vertC6

To get the moisture out of the oil the temp must exceed 185 degrees, 160-170 is way too cold. LS motors operate best at 200-210.