Why won’t my ranger warm up all the way?

[B16racereg6]

2002 v6 xlt ranger it won’t get warmer then 165deg I’ve changed the thermostat already any ideas? If I turn the heat on it runs colder. I’m stumped new to fords and trucks. The truck has 350,000 Miles it looks great and runs good. Othen the code for the coolant not getting to the correct temperature.


Any help would be great Thanks everyone.

 

[Rearanger]

I've struggled with this as well and there has been some discussion here on the problem.

You don't notice it until you install an aftermarket temp gauge as the factory gauge gives no indication. I improved the temp by installing an electric fan and insulating the by-pass hose.

I think it comes down to the metal mass of the engine and the volume of coolant in the system.

 

[B16racereg6]

My biggest issue is I can’t pass a state inspection and it’s 10 deg out I need heat. I’m going to do a full coolant flush today and maybe a heater control valve replacement.

 

[Rearanger]

I've never had an issue passing inspection here in NC, even before my electric fan. Does the inspection station just connect to the OBDII and read for any codes and confirm ready state? The engine is supposed to be closed loop at 145F.

You could try a piece of cardboard in front of the rad.

 

[B16racereg6]

Yes exactly what they are looking and the card board idea is great I’ve forgot all about that! This truck is really just a work horse beater for my home projects. But it needs to be legal for trips to homedepot ha ha!

 

[cbxer55]

Mine is a 98, never had a problem with temperature. Matter-of-fact, put a 180 in it last year, and it still seems to heat up just fine. Always plenty of hot air coming out of the vents this time of year. So much so, I drive it with the passenger side window rolled down about an inch to let some of the heat out.

Is it possible the clutch on your fan is locked up? Should be able to turn it freely when it's cold. Even so, they still move a lot of air when unlocked.

 

[adsm08]

Yeah, I would look into the fan clutch, and possibly the water pump being at fault.

If you can, try taking the fan off and seeing if that helps, before putting cardboard in front of the rad. If that is the problem it should heat up fine, and being only 10* out you shouldn't have to worry about overheating too quickly with no fan.

 

[B16racereg6]

Well everyone I put cardboard box over my radiator and my truck made it to 190 deg and that is around normal temp I’d guess I was super happy with that. So I’m guessing everything is ok just to cold in nys? Only time will tell

 

[adsm08]

No, you could still have a fan clutch stuck on. You increased the temp by removing part of the cooling surface. You haven't proven anything except that lowering the amount of airflow across the cooling surface reduces cooling, which is not exactly a novel concept in thermodynamics.

 

[B16racereg6]

I agree there is more to the story, I’m going to look more into it when it’s no longer 10 deg outside. For now I can pass the inspection and drive my truck. I will update this when I figure it out. Is the fan supposed to run at all times?

 

[adsm08]

The fan is going to spin when the engine is running, but when the clutch is engaged it is moving air around with much greater force than when it is just running along on parasitic drag.

The real test is, engine off, spin the fan by hand, and it should be pretty loose. Then get the engine up to temp, shut it off, the fan should still move, but be noticeably stiffer.

Or knock that sucker off there and see if it will warm up without the cardboard.

 

[cbxer55]

I agree there is more to the story, I’m going to look more into it when it’s no longer 10 deg outside. For now I can pass the inspection and drive my truck. I will update this when I figure it out. Is the fan supposed to run at all times?

The fan "runs" all the time because it is attached to the crankshaft. But, it has a clutch which is heat sensitive. When cold, it spins freely. When hot, not so much. If it's locked up, which can happen due to age, it will pull a whole lot more air through the radiator. And, when that air is as cold as it has been in most of the lower 48 lately, it can make a huge difference.

Like has been said, with the engine cold, you should be able to spin the fan very easily by hand. If you can't, it's in need of replacement.

 

[B16racereg6]

Awesome looking into this thanks fellas I’ve worked a lot the last few days but I’ve changed the oil the truck is doing well still. Hoping the fan isn’t junk.

 

[vetterdog]

Just a thought-I was thinking maybe your truck heats up OK but maybe your heat blend door actuator is bad? Mine was and the heat was marginal at best until I replaced the motor that opens the little door to let the heat in. Plenty of youtube vids on how to check/replace.
DV

 

[cbxer55]

The blend door on mine has been broken for years. But mine, the part the door rotates on is broken, and thus I get heat on all settings except max air. And that is typically what happens when the blend door is broken. There's a fix for it, but I haven't really lost any sleep over it. My ac quit working some time ago, and I intend to rip all the ac stuff out. Like driving with the windows down, even in my Lightning. As long as I have heat in the winter, it's all good.