Ok so today I let my car get to temperature before I head out and as I'm driving on the high way the temperature starts to do towards C.now mind you I do live in nyc and have the heat on due to it being 37 degrees here. I checked both lower and upper radiator houses and both felt some what hot. It does idle at perfect temperature until I start to put a load on it. Could this be my temp sensor and is there a way to tell if it's bad by checking voltage some how before I replace it our is it my thermostat just giving out on me slowly? Thanks in advance and wanted too get some insight so I can fix the problem tomorrow as we are expecting snow and do all my work in front of house unfortunately.

 

Thermostat stuck open most likely, or just not closing down fully. Not really a problem, it may set a code for engine temp being too low but it won't hurt anything. Fuel mileage might drop slightly but that's about it.

 

Like how cold? I mean it's going to run warmer when you're idling because there's no air passing through the radiator. Temp should always drop a bit when moving.

 

My '8 did this a month or so ago. Heater performance suffered. The car warmed up to what seemed to be within normal temperature range but when in motion, the gauge would indicate a lower temperature. I removed the thermostat and the plunger looked normal and it sat fully, but I replaced it (with another OEM) anyway. Coolant temperature gauge has been steady ever since and the heater performance is back.

 

It dulls to about here


Just sucks how this had to Happen now of all times.I really don't feel like changing the thermostat and having to re fill and bleed the system as I never dos on this car yet and heard it is a real pain.

 

Yea?I might have to do that then.I'm going out side to check resistance on the temp sensor for now.how was it bleeding the coolant system? Any recommendations? And funny thing is, is it seems to happen when the heat is on and load on the engine only.

 

I posted a pic

 

Replacing a thermostat is no big deal. Minimal coolant loss and bleeding.

 

Yea?, ok cool man thanks.I just realized I have no coolant in my over flow tank as well but coolant is up to the top in the radiator when I checked. Can you just tell me how you bled it specifically ? I'm replacing tomorrow

 

Or not...lol well to update I realized it only happens when driving on the high way..But get this,I drive on the high way both heat and ac off and it doesn't drop.soon as the blower goes on it drops whether heat or ac on.I picked up the thermostat but since it's freezing and raining here in nyc I'm going to wait and just pick up and change the coolant temp sensor as well for piece of mind.first thing though I will add coolant to my over flow tank since when I checked it is bone dry.I'll let every one know how things turn up.

 

you need to fill the overflow and rebleed. If theres a bubble, your temps will be erractic.

Start with the basics first and make sure they are 100% before changing parts.

 

Yea it was to cold yesterday to attempt although I did check over flow tank and it was a little above minimum line.I just don't get hoe after 3 years odd owning the car there's"air"in the system ya know.
So basically start the car after topping off the over flow tank to max line with the rad cap off?

 

my car used to do that, I have videos of the temp gauge moving from operating temp down to C while revving, nobody knew why. I found that it was air in the system due to being slightly low on coolant, found my radiator leaking at the seams.

 

Yea?I still haven't gotten around to checking it out I am tomorrow though hopefully.it's 12 degrees here and windy which sucks lol.

 

UPDATE!!!!!

I changed my thermostat and coolant temp sensor, added coolant to reservoir to max line and all is well. didn't have to bleed it out nothing and the car is holding prefect temperature and heat is blasting nice and hot.