NOT overheating / car not warming up

T-Flip

T-Flip

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Outside temps have been 30-50 F lately, and while driving today my temp needle never got close to the middle mark. I checked with a scanner and it never got above 170, driving around makes the temps drop a few degrees, especially on the highway.

Is this a fan issue, or a stuck thermostat? Fan seems to be on all the time but I'm not sure how to confirm this. I have no idea what is supposed to be low speed or high speed.
 
The fan runs variable speed from 0% to 100% depending on conditions.
Engaging the A/C compressor causes the fan to speed up to a minimum of 40%.
A fan running too much, to keep the engine too cold, would require the fan running full blast all the time, which you would absolutely notice. These things move a decent amount of air.
Agreed, most likely the thermostat is stuck open.
 
Thanks for the info guys. I will start with the thermostat. I'll check again with the fan if that's not it. I think it might be stuck on one speed but I'll confirm once again. Should it spin faster when I rev the throttle in park?

OE temperature for the thermostat is 192 F i believe, would you all recommend an alternate temp tstat like a 180 degree or no?
 
Maybe not a stuck thermostat, but a weak/worn one. The springs do wear out because of all the heat. Usually when they stick, (in cooler weather), you will see a spike in temp... then a sudden drop.
 
If you're going to change the thermostat I would also change the housing. I just did mine a couple months back for running hot. Turns out the housing was my issue. One of the shoulders that hold the compressed thermostat assembly broke off and it was sideways in there. I have the receipts from the previous owner and one of them is for a Motorcraft thermostat housing that is dated three years ago. I don't know positively that he installed it but I believe he did. With all the heat and pressure (spring) that it is subjected to I feel you should always change it out if you are doing the thermostat.
 
04_Sport_LS said:
Maybe not a stuck thermostat, but a weak/worn one. The springs do wear out because of all the heat. Usually when they stick, (in cooler weather), you will see a spike in temp... then a sudden drop.
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Dang mine just doesn't even get up to temp unless I idle for a long time, then when I get to driving it drops 10-15 degrees.

jerryg2112 said:
If you're going to change the thermostat I would also change the housing. I just did mine a couple months back for running hot. Turns out the housing was my issue. One of the shoulders that hold the compressed thermostat assembly broke off and it was sideways in there. I have the receipts from the previous owner and one of them is for a Motorcraft thermostat housing that is dated three years ago. I don't know positively that he installed it but I believe he did. With all the heat and pressure (spring) that it is subjected to I feel you should always change it out if you are doing the thermostat.
Click to expand...
I hope my housing is still solid because it looks like it's been replaced with an aluminum one, were the oem housings plastic? I'll inspect further when I get around to the job
 
T-Flip said:
Dang mine just doesn't even get up to temp unless I idle for a long time, then when I get to driving it drops 10-15 degrees.


I hope my housing is still solid because it looks like it's been replaced with an aluminum one, were the oem housings plastic? I'll inspect further when I get around to the job
Click to expand...
Yes plastic. If yours is aluminum I wouldn't worry.
 
Bad coolant mix ratio??? Low coolant level? Air in system? IIRC the temp is read off the Coolant Head Temp Sensor... under the passenger side of the intake manfold toward the rear.

Have you tried unplugging the cooling fan to see if the temp goes up?
 
Well, if you've got one of the old-style thermostats the rubber could've separated & jammed it open. The newer ones are revised so that doesn't happen. Any idea how old yours is?
 
04_Sport_LS said:
Bad coolant mix ratio??? Low coolant level? Air in system? IIRC the temp is read off the Coolant Head Temp Sensor... under the passenger side of the intake manfold toward the rear.

Have you tried unplugging the cooling fan to see if the temp goes up?
Click to expand...
Mine is a 01 v6 so it has a hydraulic fan. If unplugging it would stop the fan I'll try it. I did drain and fill the coolant while changing plugs & coils but I'm not sure about the ratio because I just reused the coolant since it was still good. Would having more antifreeze than water cause these issues?

04_Sport_LS said:
That sounds like a weak thermostat.
Click to expand...
I ordered an OEM thermostat from the dealership since it's not a super expensive part, I'm just waiting on them now. Motorcraft #RT1141, $23 total.

HRLNKN said:
Well, if you've got one of the old-style thermostats the rubber could've separated & jammed it open. The newer ones are revised so that doesn't happen. Any idea how old yours is?
Click to expand...
It's probably very old, I haven't touched it since my ownership 7 years ago. Maybe one of the repair shops replaced it but I can't remember that far back. Can you check to see if this is the revised version you're referring to?
https://parts.ford.com/shop/en/us/engine/thermostats-and-hoses/thermostat-assy-6323933-1
 
Yeah that's the revised version, RT1141. AFAIK the older type isn't made anymore
 
Okay fellas I replaced the tstat today. I went with a motorad ultrastat at 192 degrees since the dealer is taking too long with parts. Turns out there was a bunch of junk clogging the springs. It warmed up within minutes.

I'm in the process of bleeding right now, it's overheating at idle and ive either got low heat or intermittent heat. My engine air bleed is stuck and won't open up (v6), can I bleed properly without this? I get a steady stream of coolant next to the reservoir so I don't know what else I'm missing. I'll have to come back another day to check on it again
 
Next to the reservoir is the heater circuit bleed. It's separate from the engine air bleed. Yes, you do need that engine air bleed too, but if it's stuck the odds are good that you will break that whole piece getting it open.
Get the back of the car as high as you can with the front low. That will help. If that's not enough, then you can do it with a vacuum fill without bleeding. Some of them are fairly cheap.
 
You could try, (with a cold engine), heating the cap with a heat gun. Make a few heat shields out of several layers of, (folded), aluminum foil... to ptrotect everything around the cap. Heat just the cap for about 30 seconds... then back off for about 5 minutes. Then heat only the cap again... and back off again. Try this several times... and on the last try spray the cap with some PB Blaster... trying to soak the threads. Let it sit for 10 minutes... then try removing the cap.

You don't want to heat the whole housing. Just the cap. The heat will expand the cap... and as it cools the cap will shrink. Doing the above procedure several times SHOULD break the corrosion loose that has the cap "stuck".

Might work... or it might not.
 
The v6 engine air bleeds are plastic, I don't think torching is a good idea. I'll leave it alone for now since I think I got most of the air out.

I used the bleeder valve next to the reservoir and backed in on a hill to get air to escape like joe suggested. With the heater on max, i let it warm up to operating temp and cracked the valve until I got a steady stream.

It just needed a few cycles of letting the engine cool off and repeating the process to get most of the air out. Coolant level will drop so keep i kept an eye on that. Now I can idle and temps are steady at 220. Driving around drops it to 210-215 so I'm happy. I'll still try to bleed a few more times just to make sure though

I just hope it won't give me trouble in the summertime..
 
Thanks for all the help yall. I'm trying to rescue my neglected LS, it was my first car and I didn't know jack about maintenance when I was a teenager so it pretty much got tore up. Trying to bring her back to life slowly but surely, so there will be more threads soon.
 
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