Overheating issues

[myerzkid]

Ok guys I need some help...

I have an 04 explorer V6 and its acting strange. I live in montana so it gets cold. Coolant was low and the heater wouldn't get hot right away and would only blow hot air while we were driving. I added some coolant and viola problem solved.

Yesterday we get on the road and it was a warm day, comparatively, and we decide to take a little trip to do some shopping. we make it about 60 miles down the road and I just happen to look at the console and it tells me that I am overheating. I pull off and let it cool down. start up again and it says its temperature is in the normal range. I pull out and the heat shoots right back up.

So I turn around and go back to the nearest town after deciding that my Tstat is screwy and it needs replacing. when I get to the nearest station I decide to refill the coolant because alot had been forced out of the overflow tank. It takes and entire gallon of premix without blinking. So I add some straight coolant and alternate distilled water to get it back to a workable level.

No more overheating. Since we are closer to our destination than our origin we press on and the temp stays in the normal range. However once we get back into stop and go driving I noticed that the heater started acting funny again. It'll go cold, then hot, then cold but the vehicle stays in the normal range.

I need some help guys... Is it just the tstat... Its not leaking, I changed the housing last winter... No other fluids in the coolant...

 

[EXPLORER04]

According to the service manual these are the things to check for if overheating occurs:

Thermostat.
Coolant pump.
Internal engine coolant leak.
Radiator.
Radiator airflow obstruction.
Fan/fan clutch.
Pressure relief cap.
Airlock in the system.
Coolant condition/concentration




To check Thermostat:
Key in START position.
Start the engine and allow the engine to run for 10 minutes.
Feel the inlet and outlet heater water hoses and the underside of the upper radiator hose.
Are the upper radiator hose and the heater water hoses cold?

 

[myerzkid]

thanks... It was a faulty thermostat... stuck shut and ended up with an air pocket in the hose...

Nevermind... It did it again...

This time we started the vehicle and let idle for about a minute so that everything is flowing and then we start driving. Not speeding or accelerating too quickly... we get a quarter mile from the parking lot and the heater is already blowing fairly hot air... I look at the temperature gauge and its climbing... slowly but quicker than it should be after sitting in 36 degree weather for a couple hours. we're about a mile away and the heater goes cold... and seconds later the temperature climbs from normal operating temp to 1 tickmark below the red and the check gages light comes on. It hits the red and I tell my wife to let off the gas and slow down. she does and it stops climbing, stays in one spot for about 5-10 seconds and starts to drop. Not steady but in small chunks... it hits normal and the heater starts blowing warm air again and the temp gauge says normal again. It was about a mile from when the check gauge lit up to when the heater got warm. she had slowed down to about 35-45 mph and maintained the speed slowly giving it gas as it cooled down. once it settles at about normal again and the heat is on I tell her to give it more gas to see how it does and again no issue...

 

[cyon]

myerkid: what was the final outcome?

 

[Jasone352]

As opposed to starting another thread I figured I would just hijack this one since I am having very similar issues with the overheating. However when the temp gauge hits the red and my check gauge light comes on I notice my car seems to loose horsepower or just kind of hiccups when accelerating. The temp drops shortlly after but usually repeated this shortly after.

This happens probably two or three times a week when driving it daily. I'm have no clue what it could be and any advice would be appreciative. I will check the thermostat as stated earlier the next chance I get. Thanks

Edit: I forgot to mention that turnin the heater on seems to help the gauge go back to normal levels. Not sure if that is significant at all but figured it was worth the mention.

 

[cyon]

Sounds about the same as mine other than it would do it at time other than when the temp spiked. I replaced thermostat housing (it was warped), thermostat and temp sensor. However, I still had the problem. Then, I replaced the radiator with a new one I bought off of eBay and all has been well since. Are you losing coolant?