Known problems from a bad ECT Eng cool temp sensor. List please

Yellow302

Member
Mar 2, 2003
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NJ
My temp gauge has been going passed R before it goes to closed loop. Then the temp varrys from between N-O then up to R again. My fan seems to come on early and late, or the guage is on R and the fan isn't on. The fan realy isn't my problem right now.

I am more worryed about my car's tranny locking up before it enters closed loop. I am thinking my car thinks its hot when its cold and cold when its hot. The temp guage raises then drops the raises quickly.

I have a 192 Termo right now that I put in for the winter. I wonder if replacing the ECT that pulgs into the intake manifold will help. I thinks is like $4 from napa.
 
That sounds like what mine was doing. A new ECT should fix it.

BTW, If you turn the defrost or A/C on, the fan should kick on. That's what I did when mine started getting too hot.
 
Ok for one the temp gauge in your car and your ECT sensor are two different things. Your temp gauge is just a little sending unit in ur lower intake manifold. Your ECT is in the black coolant hard lines on the pasenger side of your intake manifold. Second how are you veryifying that you are in closed loop???
Mostly what when you have a bad ECT sensor like i did you will get a rough idle and poor drivability when the car is on a cold start up. Thats what i have and it was cured by my new ECT sensor. But your temp gauge and ECT are two different things so i tink your are getting confused.
 
WhiteDevil please can you elaborate on where the ECT is again..i asked on here where it is located yesterday and everyone told me it plugged into the lower intake manifoldI knew what they were talking about but i knew there was one in a heater or coolant line or something. Is it actually INSIDE the line or is it plugged INTO the line or something?? I am having the same symptoms that you mentioned above and i would like to get it taken care of but i cant find the ECT!! My chilton is about as clueless on the topic as i am..Please help :(
 
This is the ECT I believe.
ect.jpg
 
well i do have a ruff idel / drivablity problems with the car right now, until its warm. I belive my ECT is the problem. If my temp guage was way off then i would suspect the guage or my t stat was sticking.

Where can I get an ECT sensory any way, I checked on napa's web site and they said it was like 4 bucks
 
The ECT(engine coolant temp) sensor - is circled in the picture that low5.0 posted, that is the temp device that sends the temp info to your cars computer, so that it can adjust your idle spark and timing based on the temperature of your engine.

The Temp Sending unit - is on the front driverside part of your intake manifold. That only feeds information to the gauge in your dash board. It has nothing to do with the operation of your car.

help any?