T-stat stuck open or non existent?

[clean_86]

These last few nights of colder weather I've had no heat at all. After warming the car up for 5+ minutes I got heat out of it, until I drove 20 miles and cold again. I know my heater core is good as I get good heat out of it at times.

Is it common for these to be real problematic to get the coolant system burped? Thats the only time I have personally left a t-stat out.... Anyways hopefully this weekend I can get to throwing in a t-stat and all will be good.

[niles]

Sounds like it is either stuck open or there is air in the system. Can you hear it go "glug glug glug" when you switch the climate control to hot? If so, you may ahve an air problem.

If it overheats while sitting idle (or noticeably hotter than normal), but gets too cold while driving then the thermostat is stuck open.

[clean_86]

It will maintain normal temp sitting at idle like warming car up. Fan cycles on / off as it should. But as soon as I throw air over radiator @ 65-70 mph temp gauge drops and soon enough heater blows cold.

[niles]

When you replace the thermostat, put in a high temp thermostat. I forget if it's 180 or 195 degrees, but it will allow your coolant to get roasty toasty for maximum heater warmth. And I always bleed the air from the system a few times after a coolant change cause I'm OCD like that.

And don't get a failsafe thermostat. I made that mistake twice in a row, they fail in like 30 days, they get stuck open and its very annoying.

[Dr_Snooz]

If you have the notorious "bouncing idle," that would confirm that you have air in the cooling system.

[clean_86]

Well, no air in the system then. Idle is consistent. I'm going to tackle this here in a little bit.
There is the tiny-est miss. But I'm sure it will all work out.
O'Reilly Auto parts sold me a "Murray" T-stat. Not sure what temp.

[clean_86]

Well that couldn't have been any easier! Love the rubber "gasket" so much easier than a gasket or O ring.
My T-stat is a 192 & it puts out some COOKIN heat now.

If you have the notorious "bouncing idle," that would confirm that you have air in the cooling system.

Thanks for that, as soon as I got it in and ran it with the cap off, the idle started bouncing around. And if you hadn't said that I probably woulda worried for a minute.
When the idle started bouncing I squeezed the top rad hose to get some air/ coolant out. I also pulled the cap off of the overflow reservoir. Probably was more the top hose that did it.
Once the T-stat opened, coolant glugged down & idle smoothed out. Topped the system off, capped & test drove. Left it idling in the driveway for another 10 minutes. It stayed at normal temp, I would say I have no worries!!

[clean_86]

Oh BTW....
The T-stat was non existent. The rubber was there but that was it.

Im going to throw a gallon of 50/50 an a few tools in. Now its time for the real test.
No worries!! I have no doubts that it is fixed, But as soon as I get overconfident is when I get caught on the side of the road kicking myself in the butt.
Taking the wife out on a date probably a 100 miles of driving to & from babysitter, & dinner & back. (we live in the boonies)
Maybe now that the heater is cookin, I can get it hot enough for her to peel off some clothes

[niles]

Great to hear it worked! and wow, no T-stat...

There is also a bleed valve on top of the thermostat housing, after your car has cooled off loosen it a little to let the last bit of air out if needed.

[kkcdear]

Fan cycles on / off as it should. But as soon as I throw air over radiator @ 65-70 mph temp gauge drops and soon enough heater blows cold.

[niles]

Fan cycles on / off as it should. But as soon as I throw air over radiator @ 65-70 mph temp gauge drops and soon enough heater blows cold.

Could be a similar problem, kkcdear. I'd start with the same thing claen_86 did. New T-stat and fluid.

[RichardPrince]

The opening temp has nothing to do with how fast warmup takes. Leakage around the thermostat does. My experience is that given half a chance, a 3800 is really a very cool running engine.

Years ago we were driving from Florida to the frozen North, around sundown the TCC started dropping out. Pulled over and checked everything out and was fine, no codes. Got on the road again and lockup was back. About 5 miles later it dropped out again. Went through several cycles before I figured it out.

Turned out the thermostat (not a SuperStat) was open slightly. At Interstate speed, the engine was cooling down and when it dropped under 146F (still giving heat & ACC was compensating), the TCC would unlock. Stop to check it out and the hot soak would bring back up above 150F.