coolant temp sensor problem
 

so i bought a replacement and installed it and the guage wouldn't move. It stays all the way cold. So some guy did some little "grounding" trick and it didn't do what he wanted it to do so i returned that one and bought a replacement. It's still reading nothing. it's getting power to the connector and out the connector. I tried spraying some wd-40 in there to help it make a connection and still nothing. I'm at a loss of what to do, and i don't want to buy a new connector because you can only get them through ford and lord knows i'll have to bring my life savings if i buy it from them.

any other things i should check or try?

my son's 96 mustang gt had the same problem, he replaced the gauge and now it works.

damn, i wonder where i can find that guage and how hard it is to replace.

try the dealer or a junk yard should not be to hard to replace.

what do you mean the guage? like is there a motor behind the dash are something? i've never dealt with the guages.

Swap in a new cluster or get another cluster and swap out the pieces and see if it works then. Look at the How-To Swap Odometer thread and you will see that the gauge cluster its self is 3 pieces.

x2, try the guage. Theres a great sticky on removing the gauges, not so bad at all.

There are 2 sensors, one for the PCM (which has 2 wires in the conector) and one for the gauge, which has a 1 wire connector.

Which one did you change?

guage cluster whatever I have 79 trans am so I am use to calling them guages.

i changed the 1 wire connector on mine.

You changed the right sensor.....and grounding the wire going to the sensor doesn't make the gauge peg to HOT?

well, some other guy did it while i watched the guage, so i'm not sure if he had a good coonection. i'll try it again this afternoon with a piece wire straight to the negative terminal on the battery and i'll go check the guage. i'll let you know how it worx.

well, sure enough that some bich pegged out. So what do i do now?????

IMO the cluster is your problem.

And btw, you can read the other temp sensor with a OBD2 tool like scanguage or autotap.

Rich

What's the chances of the cluster jus stopping working when i change the sensor. I changed the sensor because everytime i ran the truck it was at a different temp. It moved before why would it just stop moving now??

stuff just stops working not always an anwser

That sensor (one wire) relies on its case getting a path to ground.

When you installed a new sensor, did you teflon tape the threads by any chance?

To continue troubleshooting, simply take a piece of wire. Touch one end of the wire to the sensor case and touch the other end to the NEGATIVE battery terminal. Does the gage work? If so, you have a GROUND problem.

You already ruled out a power problem.

You could also be fixing the wrong part. This symptom could be that the thermostat isn't closing, so the coolant never gets warm enough to register on the gage. IIRC, when the gage comes off the cold peg is ~ 150 degrees. I can check again on the drive home (compare ScanGuageII to dash gage), but this could easily be a bad thermostat.


Follow up on the temp gage:

Mine reaches the first line on the gage, (just above buried at full cold) @ 143 degrees. It appears to start moving from fully cold in the low 130s.

Just measure the sensor resistance to the engine block, or the negative battery terminal, that will tell you if it getting properly grounded or not....

i alreaady did this. you must have missed my post. i grounded to the negative terminal and the guage pegged out. so now what do i need to check now? or does the guage work right if i leave it grounded??

BUMP

CHeck your coolant mine did the same thing it was about half a quart low filled it up got all of the air out now my gauge reads fine.

hmmm, ok i'll give it a try

The reason being your coolant can be a little low and not flow by the sensor thus reading cold.

right, i understand. but i checked it and its full so another option knocked off the list