Lately my Ranger likes to overheat randomly. Its a 2001 4.0L. It only overheats randomly, the gauge will go up to 3/4 and sometimes the whole way to HOT and set off the CHECK GAUGE light. I have 60K miles on it, automatic, and an e-fan. I've had an e-fan for over a year, but this problem just started about a month ago. I've been searching on dezertrangers.com and it seems like a few people had their radiator clogged. Could mine be clogged, or the thermostat? My coolant level is fine, and I flushed it last summer. It stays fairly cool when moving at a decent speed, but when sitting/idleing it will get much higher than normal operating temp. This only happens about 1 out of 20 times driving. Most of the time its totally fine and cool, then other times it overheats and continues to overheat the entire time driving. I've seen some posts on here saying that maybe it is the water pump, but I haven't seen anyone have any luck with a new water pump for the problem at hand.

 

its the front bumper, i think i should take it off your hands.


it may be the e-fan since it doesn't happen when your moving... im not really sure tho

toss the old one on and see what happens

 

Since it doesn't do it when moving, I would say it's your e-fan, or wiring/thermostat for the e-fan.

I would save yourself some troubles, go back to the OEM mechanical fan.....

 

I've had an e-fan on for almost 2 years, and never had any problem of this sort, in everyday normal driving situations. I know for a fact that it's not the e-fan. And, I do check to see if the fan is working when the overheating occurs, and it does. (I pull over and literally check)
I'm leaning toward the thermostat. It only happens randomly as I said, like as if the thermostat mechanics are dying.

 

I agree, changing the T-stat is the first thing you should try. But I'd be eyeballing that e-fan, too. Not just whether it's working, but how much air it's pushing (pulling?).

 

pulling... i hope haha

 

Yes, it's set up as pulling. It doesn't overheat all of the time. I can beat on it some days and it will run at normal temp, but on a random day, it will decide to get hot, and stay hot until I am done driving it.
When it gets really hot, I can hear and feel a slight click from the engine bay, like the water pump has stopped. Also when this happens the AC doesn't work. The AC is probably really hot also at this time which is why it doesn't produce cold air. I'm thinking it's the thermostat being faulty, and causing the water pump to shut off the coolant.

 

sounds like an efan problem

my efan stopped pulling the required CFM, and overheated.

then my efan started blowing fuses.

cheap easy way to make sure if something electrical is replace the relay and the fuses.

 

I have a 20A fuse on the power for the e-fan, it has never blown. The fan sounds just as loud as when I got it so I doubt it lost any great amount of CFM's if any.
If it's not the fan, what else could it be?

 

I say next time it happens pull right over. Pop the hood and check the fan. That should give you a better idea about the fan. If you didn't have the efan I would think the problem would be the thermostat.

You may want to check and make sure there isn't dirt clogging your fins on the radiator also.

Just read some other posts in the thread. CHANGE THE THERMOSTAT. It is prolly shot.

 

I have pulled over when it overheated to check and make sure the fan was working, and it was every time.
I searched this site and found no direct correlation to my problem, nobody seemed to figure out their problem either to help me out.
There is not dirt clogging my fins, it's super clean.

 

i guess i would resort to the t-stat then.

the water pump is not seeping fluid is it?

 

It's not as far as I know of. The coolant level hasn't changed, I check that also to see if it would be leaking or causing a depressurization some how.

 

ah could be radiator cap too.

atleast yours is keeping fluid.

mine overheats and runs through coolant.

 

This is really easy. They key is that your AC stops working as well! This has nothing to do then with the water pump, radiator, or engine thermostat. This is simply the E-Fan not turning on. There are a lot of total crap e-fan controllers out there and this is exactly what they do. I had one too. Without the fan running while you aren't moving, there will be no air flow across the AC condenser or the radiator. You overheat and your AC stops working. I 100% guarantee you that next time you have this happen, stop and get out of the truck and you'll see that your E-Fan isn't running.

 

It's not that the AC totally stops working. It will for a few minutes on and off. I'm pretty sure that the fan is still running when the AC quits, I have a switch in the cab to kill the fan, and I tried turning it off and on and can feel a slight vibration when it is on, and I could feel the vibration when the AC was out. It does make sense though, i'll have to check for sure next time it occurs.

 

It it doesn't overheat running on the highway, then the problem isn't the thermostat!!! The PCM will shut the AC compressor off (with the WOT relay) if the ECT sensor says it's overheating.

 

Yea, the AC will stay off until it starts getting air flow again. It doesn't kill it all together.

 

Perhaps a faulty ECT sensor? I had one on a car the other day, a saturn I believe, that would over heat at random however the temp would say its below 210 like around 180 or so but the coolant would boil out.

 

It does get hot when driving on the highway, aka driving fast enough for the fan to not work but incoming airflow cooling the radiator and engine. It gets hotter than the normal temp in the situation, it will just get much hotter when sitting or driving slow or in traffic, because the air under the hood is not moving at all.

 

just put a sump pump in a 5 gal bucket a water an hook 'er up. Works like a charm!

Joe, you goin to jon's tonight?

 

A t-stat is what 12 dollars from napa, it wouldn't hurt to start there.

 

I changed the thermostat last night, to a stock 192 degree one from AutoZone. I also drained some old fluid and put in a bottle of Water Wetter. I only had one drive with the new thermo going to work this morning, i'll keep you posted on how it works in the sweltering heat situations.

 

Also on my way home from work, it overheated, and it was 94+ degrees outside. I pulled over in a parking lot when it was hot to check over the whole system. The A/C did stop producing cold air, the e-fan was running, the rubber coolant tube/hose that runs to the top of the thermostat was pressured a little, as I couldn't completely compress it with my hands. Is that normal?

 

Re-read my earlier post!!!!!