Temp sender not working

[2.9._ranger]

I’ve read through everything I could find and nothing is helping me I just replaced my thermostat with a 180 degree one and got a new temp sensor and sender but my temp gauge isn’t moving past the C I’ve tried grounding the sender wire and it makes it go up to H so I know the wire is working I’ve cleaned the threads in the lower intake to make sure the sender is getting a good connection but I’m still not getting a reading does anyone know what’s going on

 

[rusty ol ranger]

I’ve read through everything I could find and nothing is helping me I just replaced my thermostat with a 180 degree one and got a new temp sensor and sender but my temp gauge isn’t moving past the C I’ve tried grounding the sender wire and it makes it go up to H so I know the wire is working I’ve cleaned the threads in the lower intake to make sure the sender is getting a good connection but I’m still not getting a reading does anyone know what’s going on

Threads have teflon tape on them?

 

[2.9._ranger]

Threads have teflon tape on them?

No the threads are bare

 

[Brain75]

Are you sure it is a real temp gauge and not an idiot light "centered needle". Temp gauges haven't been real gauges since like '79-82 depending on truck/van/car within ford. It's an idiot light disguised as a gauge. I don't think any ranger ever made had real gauges. Is this new sensor and sender still an OEM or an aftermarket cluster?

If your old gauge worked then what you need is either to add or replace the resistor to get the right resistance, or replace the sending unit with a 180 degree sending unit, one that will provide the right resistance signal for the temp you are running. Probably can return the new gauge and sending unit and just get the right sending unit.

 

[2.9._ranger]

Are you sure it is a real temp gauge and not an idiot light "centered needle". Temp gauges haven't been real gauges since like '79-82 depending on truck/van/car within ford. It's an idiot light disguised as a gauge. I don't think any ranger ever made had real gauges. Is this new sensor and sender still an OEM or an aftermarket cluster?

If your old gauge worked then what you need is either to add or replace the resistor to get the right resistance, or replace the sending unit with a 180 degree sending unit, one that will provide the right resistance signal for the temp you are running. Probably can return the new gauge and sending unit and just get the right sending unit.

The gauge is original and the old sender was working until I replaced the thermostat but now it’s not working and not even the new ones working do you think it’s worth it to chase down this problem or should I just wait and get an aftermarket gauge?

 

[Brain75]

On a real gauge (before 1979) the temp would climb slowly as the engine heats up. With these the temp will stay cold until it reaches "something" - probably 185-190, then suddenly snap to a centered needle and stay there as long as it is 192+/- 5 maybe 10 degrees. It's not a real gauge, it is a switch/idiot light that looks like a gauge. Since the new needle and the new sensor are spec'd the same as OEM they behave the same - they will not ever show a reading until you get well past the 180 your new thermostat is set to. Put your old thermo in if you want to verify what I am saying once you reach "warm" the needle will snap to dead center of the range. - same thing with oil, in the first 5 seconds of running while the engine is building pressure a real analog gauge will slowly move the needle. These new gauges don't, they just snap to center when you are "close to normal". I don't know the part number for a low temp sender that will provide the correct resistance - I just spent a few minutes looking on parts geek, and all of em don't specify or do say "conforms to OEM specs" (192 degrees) none of em list the temperature they close the circuit at.

 

[2.9._ranger]

On a real gauge (before 1979) the temp would climb slowly as the engine heats up. With these the temp will stay cold until it reaches "something" - probably 185-190, then suddenly snap to a centered needle and stay there as long as it is 192+/- 5 maybe 10 degrees. It's not a real gauge, it is a switch/idiot light that looks like a gauge. Since the new needle and the new sensor are spec'd the same as OEM they behave the same - they will not ever show a reading until you get well past the 180 your new thermostat is set to. Put your old thermo in if you want to verify what I am saying once you reach "warm" the needle will snap to dead center of the range. - same thing with oil, in the first 5 seconds of running while the engine is building pressure a real analog gauge will slowly move the needle. These new gauges don't, they just snap to center when you are "close to normal". I don't know the part number for a low temp sender that will provide the correct resistance - I just spent a few minutes looking on parts geek, and all of em don't specify or do say "conforms to OEM specs" (192 degrees) none of em list the temperature they close the circuit at.

So is it possible that it works I just didn’t let it heat up enough for it to kick on?

 

[2.9._ranger]

Nvm I don’t think it’s that I let it get pretty hot and nothing happened

 

[Mechrick]

old sender was working until I replaced the thermostat but now it’s not working

It's not impossible to get two bad thermostats in a row. And, on some vehicles, it's possible to get them in backward. Make sure the pointy end points toward the radiator upper hose.

To check for a bad thermostat if you don't have an infared pyrometer, slide some cardboard in front of the radiator and run it for a bit (10 minutes or so, watch for signs of overheating). If the stat is stuck open the temp will come up.

Are you sure it is a real temp gauge and not an idiot light "centered needle"

AFAIK, that was only oil pressure gauges.

 

[2.9._ranger]

It's not impossible to get two bad thermostats in a row. And, on some vehicles, it's possible to get them in backward. Make sure the pointy end points toward the radiator upper hose.

To check for a bad thermostat if you don't have an infared pyrometer, slide some cardboard in front of the radiator and run it for a bit (10 minutes or so, watch for signs of overheating). If the stat is stuck open the temp will come up.



AFAIK, that was only oil pressure gauges.

I’m pretty sure my thermostat is working but when I block the radiator with cardboard like you said the upper coolant hose gets hot but idk if that means anything I got the temp gauge to give me some type of reading now it’ll read under the n on normal but won’t go any higher than that even with the engine running

 

[Uncle Gump]

With a test light... connect one end to B+... the other to the temp sender body. The test light should illuminate.

If it doesn't... run a ground jumper to the sender body. See if the hauge reacts. It should.

 

[2.9._ranger]

Idk what I did but now when I leave the engine running it slowly climbs but I’m not sure if it’s reading accurately

 

[2.9._ranger]

It’s acting really weird it got up to the o then drop to the n then climbed back up to the middle of the o and wouldn’t go up any higher than that and when I turn the truck off then turned the key to on it sits in the middle of the n

 

[Uncle Gump]

Don't over think it.

Do you have hood heat?

Put some time on it and get use to it. If it goes put of what you consider it's normal range... look fir a problem at that point.

I'm not a big fan of the factory gauges. It's usually the first thing I do is add aftermarket gauges.

 

[2.9._ranger]

Don't over think it.

Do you have hood heat?

Put some time on it and get use to it. If it goes put of what you consider it's normal range... look fir a problem at that point.

I'm not a big fan of the factory gauges. It's usually the first thing I do is add aftermarket gauges.

My hood is off right now and the reason I think it’s not reading right is because my engine is extremely hot to the touch like more than I think it should be and it’s taking a long time to cool down I’m trying not to overthink it but I’ve been working on this thing for a year and a half now