Timing belt broke on my nephew's 98 2.3L Ranger. Went ahead and replaced the water pump and thermostat while replacing the belt. The original thermostat was rusted apart, came out in two pieces. The new one didn't fit the way I would think it should, it was loose in the housing, but I went ahead and installed it anyway.

The temp. gauge on the dash stopped registering anything after reassembly. I jumped a wire across the leads and confirmed that the dash gauge does work. Ran the engine, confirmed the thermostat opened, drove the truck, and had good heat in the cab. I assumed that the temp sensor bought the farm during disassembly.

He's been driving the truck for few days and now has no heat in the cab. I was planning on replacing the temp sensor today, but now it sounds like the thermostat is stuck open.

Should the Thermostat fit snuggly into the housing, and will the wrong thermostat effect the temp sensor?

Thanks for reading, can use all the kelp I can get.

What is the brand and part # of the stat you used?...it needs to fit properly. FYI: You have the 2.5.

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Ford Ranger, 1998, Reg Cab, 2WD, 5 speed, 4 cylinder, 140k

You probably won't want to hear this, but Rangers are picky little trucks. If you didn't put a Motorcraft thermostat in it, you'll probably have problems.

If you enter thermostat in the search section and look around, I think everyone will agree with that thought. Try that first.

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2005 2.3L XL 5SOD 3.73 K&N
KYB Shocks Husky Toolbox
Alpine / Rockford Fosgate Sound

"Ask me about my AC Vent fix!"

RangerSchool
I don't have the part number, My nephew bought it at NAPA and threw out the box. I THOUGHT it was a 2.5, but he keeps telling me it's a 2.3. Thanks.

Mike in BAMA
Yea, I read that in a couple of places. Would a loose fitting thermo make the sensor totally crap out? It doesn't move at all, acts like its disconnected.
Thanks

The 2.5 is the same engine as the 2.3 just with a better head and I think a longer stroke.

the tstat would not make the sensor fail........I will tell you that if your coolant is low the sensors will not be submerged and when you raise the rpm/waterpump the coolant will flush over the sensor and they will "change" the reading.....put your scanner on it and see if the ECT is working......

the tstat needs to sit tight in the housing...I think it even twists in slightly......and as stated you want a motorcraft....at this point if your coolant is full and burped I would go get a new stat......put the jiggle valve at 12:00.........get all the air out and you should be all set.......a lot of people cover the radiator in the winter......these engines run cool ....

I think it has been cold in TN..the tstat might be so loose that coolant is running right to the rad and never heating up ......this could be keeping the gauge in the cold area....

make sure he has a 1998 and not and a 1997 that has the 2.3

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Ford Ranger, 1998, Reg Cab, 2WD, 5 speed, 4 cylinder, 140k

just thought of something.....i would establish for sure that you have a 1998 2.5........and not an earlier 2.3.........I believe the timing belts and water-pumps are the same for both motors but the tstats are different......the 2.5 has the tempgauge sensor and the ect sensor right next to each other on top of the tstat housing.....the 2.3 I think has one sensor in the housing and one in da head....I think

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Ford Ranger, 1998, Reg Cab, 2WD, 5 speed, 4 cylinder, 140k

Update: Pulled the old tstat and found the gasket dislodged and stuck further up the housing. The Ford dealer said that they have a patent on the design and no after market part will fit the same as theirs. Unfortunately they didn't have any in stock so I had to try another one from a different parts place. This one had sticky tape that adheres to the tstat housing and no jiggle valve.

I did get the temp gauge to work by replacing the sensor, but couldn't get proper heat to the cab. It's either got air in the system or the tstat is stuck open. My nephew had to leave so I'm not sure yet. I'm going to try and burp it some more tomorrow. When the engine is revved, the heat blows warmer, but never gets hot. When I squeeze on the top hose, the temp gauge fluctuates.

Both sensors are right next to each other on the tstat housing, Thanks for helping me confirm it's a 2.5.

Stant is the next best option. also next time if you don't have a jiggle valve drill a small hole in its place.

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Ford Ranger, 1998, Reg Cab, 2WD, 5 speed, 4 cylinder, 140k

My Stant TStat had a rubber seal around it stays in the housing nice and tight and jiggler valve. And my 2.3 has both sensors on the TStat housing.

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97 ranger reg cab 2.3 5 speed. 2 wd no ac. Mods after market jvc head unit & throttle cable. 06 mirror upgrade.

Sounds like the OP should run the VIN.

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If the gauge fluctuates when you squeeze the hose then your fluid is low or you have an air bubble.

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Ford Ranger, 1998, Reg Cab, 2WD, 5 speed, 4 cylinder, 140k