I have a 1985 SR5 4wd w/22RE engine. The water temp gauge is very erretic. It will go from no indication to about halfway then drop back to nothing and then it seems to act normal and then move back to the halfway point. Any thoughts

 

My guess is a sending unit, but you can eliminate your gauge as the source of failure my metering out the terminals on the back of the instrument panel.

IG - TU = approx 135 ohms
TU - E = approx 138 ohms
IG - E = approx 273 ohms

I would also check the wire from the sending unit to the gauge.

You can check the resistance of the guage to ground. It should be approx 24 ohms hot (220 degrees) and approx 150 ohms cold.

 

did you recently change the antifreeze?

does the vehicle idle act up at same time this is occurring?

could be just an air bubble passing by the temperature sensor.

don' t just start throwing money and parts at it. Let's talk this out a bit more

 

had a similar problem on my 84 runner.......problem was with the temp gauge it self. gauge needle would bounce around and read temp then would drop to zero. remove and replaced the temp gauge.

 

This is a fresh rebuild. Prior to installing the motor the same thing was happening. The temp sending unit has been changed. I have not checked resistance on the gauge cluster. Nothing seems to be running abnormally hot. I can grab all the hoses and not get burned. I have tried to burp all air out of the system by being on a hill and squeezing hoses and everything else I have read. I do not want to take a chance on doing damage to the fresh motor

 

The idle does not change

 

http://www.4crawler.com/4x4/CheapTri...tml#Thermostat

stat installed the correct way?

 

If you replaced the sending unit, all you're left with is the wire from the sending unit to the gauge and the gauge itself. All the gauges use the same power and ground, so its probably not that. Sounding more like a gauge.

 

if you ground the wire to the sensor the gauge needle should move all the way to the top. from the sound of it looks to be the gauge my did the same thing where the needle would jump around from normal to not reading anything. just got tried of it and changed out the gauge.

 

If it is the gauge. How do you remove it from the cluster.

 

remove the cluster and from dash
remove the top mounting bracket from the cluster
remove front clear plastic face
back of panel will be phillip head machine screws to hold and connect the gauges to the ribbion tape. will be easier if the tach is first them remove the water/oil gauges.

 

Can you still get new gauges?

 

need to check with the dealer...........if available it won't be cheap.

 

Any suggestions? Aftermarket in a different location?

 

what i did was to find another instrument panel and removed what was needed.

 

Getting one from a wrecking yard will be a crap shoot at best.

 

check you pm

 

Thanks will see what happens. I was thinking of putting in a small gauge cluster in the front section of the console under the radio. Please pm again with the e- address

 

pm sent..........aftermarket will most likey be cheaper