Does anyone know which pin input goes in the ecu from the rear water temp sensor. Thanks for the help.

 

can anyone please help Ive searched and cant find anything

 

Check the first post on page 3 of this thread https://www.rx7club.com/forum/showth...g&pagenumber=3

It looks like its the yellow and white wire.

 

The rear water temp sensor? You mean the one just above the spark plugs? It only goes to the gauge. The ECU uses the one on the filler neck.

 

now im confused my water temp readings are all messed up. I have THe power FC and if I look at water temp it doesnt change but I dont have the rear sensor hooked up bucause the wire felt the need to disappear on me. I have the front one hooked up. All Im trying to do is make my fan speed change with water temp. Now the only way my fans come on is if I push the AC button but I dont have AC. If something is bad what. If you could let me know. Thanks.
TJ

 

The PFC uses the sensor on the filler neck. Unless you get the car really hot, the fans will not even come on. You could check the coolant filler neck sensor connection, to make sure it's not corroded. I'm sure there is a way to test the sensor as well, in fact, I'm sure the PFC does this when you first turn on the key. Does the "Exhaust overheat" lamp come on when you start the engine? If so there is a sensor failure. What temp. does the PFC report. Most get 88C. It can fluctuate up past 100C, and of course will start out down at 30C or so when you start a cold engine. Check the coolant level in the engine (when cold). It should be down only 2" or so in the filler neck on the engine.

 

I know coolent level is good because its a predrive ritual to check it. it goes from like 30-40 C. And yes the exhast heat light never turns off I always wondered what does this mean how can I tell which sensor is bad. Also cant I change the fan tempature trun on point with PFC. So what now buy a new sensor ?? that thing looks prue evil to change.
Thanks for the help

 

It isn't hard to change that sensor. May have to remove the alternator. Drain coolant from radiator first.

Note that this sensor is exactly the same one used for fuel thermosensor.

But my guess is your wiring harness or connector, not the sensor.