94 Explorer Desperately need help
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From: Buckingham USA
94 Explorer Desperately need help
I have 53,000 orig. miles the temp gauge goes from dead center to redline and back. Then it will constantly go to the L and back to center. The temp goes from 195 to 240 degrees in 10 seconds and then back to normal. I have had the thermostat replaced twice, put in a temp gauge and sensor package, a new water pump, a new radiator all new hoses, and went through all diagnostics and everything reads normal. But temp gauge fluctuates like crazy and constantly reads hot. I have invested almost $1000 within the last two weeks. Does anyone have a clue??????
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94 Explorer Desperately need help
you may have already done this but it almost sounds like you have air trapped in you system, take you radiator cap off and let it run, once the thermostat opens if there is air in it antifreeze will "burb" out the hole. I had that problem after I put a frost plug heater in one of my cars when I was younger, and I had the same symtoms you described.
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Joined: Jul 1999
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94 Explorer Desperately need help
Are you losing any coolant ? The intake manifold gaskets on those engines are trouble spots & a lot of them leak . Running your engine up to 240 Deg is getting very close to the point where head / head gasket damage will occur .
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From: Buckingham USA
94 Explorer Desperately need help
Not loosing any coolant....mechanic not yet convinced it's the head gasket, since we would be looking at approx $1700. I Took off the radiator cap and ran it at idle, maybe to release any air pockets, but temp gauge is still going to the L in normal. Most of the time now it will run with the needle on the O of normal. Then there is this quick burst to the L or to the end mark before it red lines. It's just a matter of seconds then it's back to normal.
Tom
Tom
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94 Explorer Desperately need help
That sounds more like a gauge , coolant temp sending unit , wiring problem . Verify the coolant temp with an external thermometer . I would think if you have truly gone to 240 Deg it wouldnt take long before evidence of head gasket failure occured . Plus about the only way the coolant temp would change that quickly would be if a rad hose broke & that would be very evident .
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From: Buckingham USA
94 Explorer Desperately need help
The temp gauge and sending unit package that was recommended to replace on TSB from ford had been replaced two weeks ago. My other question is since this is the third thermostat that has been replaced since Sept. when the radiator was replaced, does it need to be a ford thermostat? All three have been NAPA! I don't know, just shooting in the dark.
Tom
Tom
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94 Explorer Desperately need help
I doubt you got that many bad thermostats . Do you know what the Tsb number of the work you had done ? I looked thru the Tsb's & nothing jumped out that seemed related to your problem . When & how did this problem begin ?
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94 Explorer Desperately need help
Can you verify that the engine is really getting that warm and cooling off that quickly? I suspect the engine may be normal, and you have a bad/loose wire from the sending unit, or a defective gauge, or somewhere in between.
If the engine is really that hot you could tell it as soon as you opened the hood.
Agreeing with an earlier poster, I have had experience with the air trap problem several times. After changing theromstats several times on one vehicle, I drilled a 1/8 " hole in the top of the thermostat so air (steam actually) couldn't get trapped in there, and it solved the problem.
Good Luck.
Winford
If the engine is really that hot you could tell it as soon as you opened the hood.
Agreeing with an earlier poster, I have had experience with the air trap problem several times. After changing theromstats several times on one vehicle, I drilled a 1/8 " hole in the top of the thermostat so air (steam actually) couldn't get trapped in there, and it solved the problem.
Good Luck.
Winford
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From: Buckingham USA
94 Explorer Desperately need help
Article No. 95-18-5
Temperature Gauge-Fluctuation/Inaccurate
It started last summer reading between low and middle of gauge. Radiator was replaced due to hole in radiator and at same time replaced thrmostat. After that the temp reading started to read from the middle of the gauge to about the A in NORMAL. This happened within a month of the replacement. So for about 2 months it ran this way and then I had the sensor and temp gauge pkg relaced. I just replaced the water pump due to another TSB.
As far as temperature readings it was registered by a infrared laser...when the readings were going up it was confirmed by pointing the gun to the manifold....I believe. I just backtracked and took out the radiator and had it tested and double checked. Everything checks out ok, but still the temp gauge will fluctuate and read hot...just before the redline.....today. My next step is to take it to a Troubleshooting Specialist, if there is such a person. It seems 4 mechanics are stumped.
Temperature Gauge-Fluctuation/Inaccurate
It started last summer reading between low and middle of gauge. Radiator was replaced due to hole in radiator and at same time replaced thrmostat. After that the temp reading started to read from the middle of the gauge to about the A in NORMAL. This happened within a month of the replacement. So for about 2 months it ran this way and then I had the sensor and temp gauge pkg relaced. I just replaced the water pump due to another TSB.
As far as temperature readings it was registered by a infrared laser...when the readings were going up it was confirmed by pointing the gun to the manifold....I believe. I just backtracked and took out the radiator and had it tested and double checked. Everything checks out ok, but still the temp gauge will fluctuate and read hot...just before the redline.....today. My next step is to take it to a Troubleshooting Specialist, if there is such a person. It seems 4 mechanics are stumped.
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From: Texas panhandle
94 Explorer Desperately need help
Is it rpm related? I had a 460 that would do the rapid temp change thing. I tried t-stats, belts, hoses, you name it, nothing worked. It would run cool at low speeds and then heat up suddenly at highway speeds. It might run 5 miles or 50 between hot flashes. Finally, I replaced the "new" water pump with another "new" one and it fixed the problem. I think the impeller was the wrong one. Some waterpumps rotate clock wise and others rotate the other way and I think some manufacturers get them mixed up.
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From: Buckingham USA
94 Explorer Desperately need help
I replaced the water pump with one that was required per TSB, larger unit. Still have problem. I do appreciate everyone's input, I'm trying everything. Thanks.
Tom
Tom
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94 Explorer Desperately need help
Winford,
Just a follow up... I had replaced thermostat for the 3rd time with one that has a opening at the top that automatically opens and closes to release air pressure. Fluctuation still occurs, but not as often or as extreme. I guess this is the best it's going to get. Overall the truck is running OK. The thermostat stays in the normal range and moves periodically to the L. It has not redlined.
It will however, go to the endline before the red every morning after i start it up and drive about 1-2 miles. After that for the remainder of the day it stays within the full normal range. If anyone know anything else that might keep the gauge from moving, please let me know. Thanks for the help.
Tom:-
Just a follow up... I had replaced thermostat for the 3rd time with one that has a opening at the top that automatically opens and closes to release air pressure. Fluctuation still occurs, but not as often or as extreme. I guess this is the best it's going to get. Overall the truck is running OK. The thermostat stays in the normal range and moves periodically to the L. It has not redlined.
It will however, go to the endline before the red every morning after i start it up and drive about 1-2 miles. After that for the remainder of the day it stays within the full normal range. If anyone know anything else that might keep the gauge from moving, please let me know. Thanks for the help.
Tom:-
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Joined: Mar 2002
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From: Mountain Home USA
94 Explorer Desperately need help
If anyone know anything else that might keep
>the gauge from moving, please let me know. Thanks for the
>help.
>Tom:-
You could take your dash apart and glue the needle down, then the gauge wouldn't move as u desire.
Just kidding..... I hope you find it. I am interested in what it ends up being.
[br]
[br]Randy - Just another Ford Lover
>the gauge from moving, please let me know. Thanks for the
>help.
>Tom:-
You could take your dash apart and glue the needle down, then the gauge wouldn't move as u desire.
Just kidding..... I hope you find it. I am interested in what it ends up being.
[br]
[br]Randy - Just another Ford Lover