2000 Ranger 6cyl, 3.0L
-In september my water temp gauge started fluttering. I replaced the thermostat and it got me through a 2 hour drive. Problem wasn't fixed so took it to the shop. The shop replaced the coolant temp SENDER (between thermostat and radiator) and ever since then my water temp gauge has riddn BELOW C, my heat isn't hot and my fuel economy has gone down. I only decided to do something it about it this past weekend. I flushed the radiator multiple times and got some of the gunk out of there (though there is still some there). I then replaced the coolant temp SENSOR after a check engine light told me that was the problem. Check engine light went away however the water temp gauge still reads BELOW C. This leads me to believe the needle to the temp gauge is broken however whenever I crank it up the needle rides a quarter-inch under what it sits at when the truck is off (default). TO RECAP

Problem- Water Temp Gauge reads BELOW C

What I've done that hasn't fixed the problem- Replace coolant sender and sensor, flushed radiator, gotten a new thermostat.

Anyne have an idea of what's up?

 

Welcome to the forum

The 2000 ECT SENDER will have a red/white stripe wire and a black/white stripe wire

Get a jumper wire, smaller diameter wire

Engine off
Key off
Pull off sender connector
Put jumper wire on the red/white wire and ground the other end of the jumper wire, battery negative is fine if your jumper is long enough

Turn on key, engine off
Temp gauge should go to HOT, red/white wire and gauge are OK
Key off
Now put jumper wire between red/white and black/white wire(black wire should be a ground)
Key on
Gauge should again go to HOT, black wire is a good ground, replace sender, don't care if is NEW, its either the wrong one or bad

If black wire is not a good ground then easiest thing is to cut it and splice it to a new ground wire that you run

If gauge doesn't move at all then get a Volt meter and test the Red/white wire, should see 12volts, if not wire is broken or cluster has a broken connection, you will need to pull out the cluster

 

Thanks Ron.