Engine does not cool down when parked overnight

[eggsalad]

2017 2.5 N/A, 47k miles

Bear with me, this is the strangest behavior I've encountered in many years of car ownership.

Get home at 6pm. At 7am get into the car, coolant gauge still indicates 170-180 degrees F. Engine gets up to operating temperature almost immediately. Okay, maybe it's the temperature sensor? Nope, checked it directly with a thermometer, indicates about the same temps, 170-180.

Checked again this morning, after 36 hours of not driving. Coolant temperature still well above ambient air temp, 130F

When driving, the coolant temperature never goes above normal.

I've never seen any car engine behave like this. Anyone got any ideas??

 

[N7turbo]

When driving, the coolant temperature never goes above normal.

This is the giveaway. Faulty thermostat. Search discussions here about it.

 

[eggsalad]

I don't understand. If it was a faulty thermostat, the operating temperature should be below normal. And how would a faulty thermostat prevent cooldown when the engine is off?

 

[N7turbo]

I don't understand. If it was a faulty thermostat, the operating temperature should be below normal. And how would a faulty thermostat prevent cooldown when the engine is off?

Are you sure that it's not cooling down? Maybe the reading is faulty.

And I thought you said the temperature never gets up to normal. That is a common symptom of the thermostat issue. Reading it again, that may not be your problem.

 

[eggsalad]

shh... don't tell "the boss" that I "borrowed" 2 different thermometers from the kitchen to triple check. Don't worry, I washed them off really well before I put them back

 

[stickerbush]

shh... don't tell "the boss" that I "borrowed" 2 different thermometers from the kitchen to triple check. Don't worry, I washed them off really well before I put them back

How exactly are you checking temperature with a thermometer? It is not possible that your engine remains warm overnight.

 

[Frankiestoy]

How exactly are you checking temperature with a thermometer? It is not possible that your engine remains warm overnight.

I agree, its not possible for a coolant system to maintain a temperature without a heating source such a running engine. While im not a mechanic this seems like common sense…

 

[Conrad 16.5]

Are we being trolled here or what?

No way that motor remains hot/warm overnight.

130 degrees after 36 hours with the motor off? Your thermometer ain't right. Can you hold your hand to the block at that temp?

I'm calling BS on this one.

 

[Jmaz]

Are we being trolled here or what?

No way that motor remains hot/warm overnight.

130 degrees after 36 hours with the motor off? Your thermometer ain't right. Can you hold your hand to the block at that temp?

I'm calling BS on this one.

Ha-Ha. This is hilarious. I've been watching this thread develop. IF ( that is IF this isn't trolling) then it makes me wonder about what is being taught in school these days or common sense observation.

 

[Conrad 16.5]

2017 2.5 N/A, 47k miles

Bear with me, this is the strangest behavior I've encountered in many years of car ownership.

Get home at 6pm. At 7am get into the car, coolant gauge still indicates 170-180 degrees F. Engine gets up to operating temperature almost immediately. Okay, maybe it's the temperature sensor? Nope, checked it directly with a thermometer, indicates about the same temps, 170-180.

Checked again this morning, after 36 hours of not driving. Coolant temperature still well above ambient air temp, 130F

When driving, the coolant temperature never goes above normal.

I've never seen any car engine behave like this. Anyone got any ideas??

You married? Who else has a set of your keys?

Perhaps someone is using your car while you sleep? Better check the mileage!!!

 

[RobertJT]

You need one of these.