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- Joined
- Jan 15, 2011
- Messages
- 10
- Reaction score
- 0
- Points
- 0
- Location
- Camp Lejeune, NC
- Vehicle Year
- 1992
- Make / Model
- Ford
- Engine Size
- 4.0L
- Transmission
- Manual
After several days of frustrating problem solving in dealing with the 'fluctuating temperature gauge on my 1992 Ranger 4x4 with the 4.0, finally figured it out.
Im not sure how often this issue occurs and only found a couple posts in dealing with this matter so here is what I went through, replaced and troubleshooted on.
First - i replaced the thermostat with a temp rating at 198 degrees, drained all the old anti-freeze and filled with new. that didnt fix the problem. Bled the coolant system by letting the truck run for 15-20 minutes to where the thermostat fully opened leaving the radiator cap off, then topped of the radiator and put the cap on. drove the truck around and the temp gauge would rise to the top of the "O" and with 10 seconds would drop below the "N" on the gauge.
Second - I replaced the temperature sensor unit thinking that it may have been the cause of the problem and wasn't.
Finally - i replaced the temperature switch located above the thermostat to the left. ran the truck as i did before to bleed the coolant system of all air bubbles, topped of the radiator and the overflow tank and ran the truck a few miles down the road and back. This time the temperature gauge needle sat right on the "O" position on the gauge with minor movement up and down but never dropping below the middle of the "N" and never rising about the "R" but the time between the movement is un-noticeable.
Hopefully this will help someone out down the road. and if there are anyother questions or need some greater detail on anything let me know.
92dangerrangerCO
Im not sure how often this issue occurs and only found a couple posts in dealing with this matter so here is what I went through, replaced and troubleshooted on.
First - i replaced the thermostat with a temp rating at 198 degrees, drained all the old anti-freeze and filled with new. that didnt fix the problem. Bled the coolant system by letting the truck run for 15-20 minutes to where the thermostat fully opened leaving the radiator cap off, then topped of the radiator and put the cap on. drove the truck around and the temp gauge would rise to the top of the "O" and with 10 seconds would drop below the "N" on the gauge.
Second - I replaced the temperature sensor unit thinking that it may have been the cause of the problem and wasn't.
Finally - i replaced the temperature switch located above the thermostat to the left. ran the truck as i did before to bleed the coolant system of all air bubbles, topped of the radiator and the overflow tank and ran the truck a few miles down the road and back. This time the temperature gauge needle sat right on the "O" position on the gauge with minor movement up and down but never dropping below the middle of the "N" and never rising about the "R" but the time between the movement is un-noticeable.
Hopefully this will help someone out down the road. and if there are anyother questions or need some greater detail on anything let me know.
92dangerrangerCO
