Where does the ECU receive it's engine temp readings?

**97AutoXVette** · 03-02-2014

I know there is the temperature sensor located just under the thermostat and I also know this is what corresponds to the temperature shown on the gauge in the instrument cluster in the dash. Is there a different sensor that the ECU reads which controls the fans and other engine parameters? If so, where is it located?

Thanks!

**Scottydoggs** · 03-02-2014

thats the only one. under the t stat, it sends 2 signals so chances are its bad.

there is a outs side temp sensor that can play with the fans. this only applies if your out side temp is reading way wrong. this sensor is located in the front bumper clipped to the rad support.

**97AutoXVette** · 03-02-2014

Also, I can tell 160 corresponds to 210 on the dash because I can see that the 160 t-stat is opening when the gauge hits 210 initially upon start-up / warm-up. The gauge gets to 210 and then drops about 5 to 10 degrees, just as it usually does when the thermostats open for the first time.

**97AutoXVette** · 03-02-2014

Interesting.. the housing on the temp sensor below the t-stat was cracked, so I replaced it. Now my temp gauge is reading very high (installed a 160 but reading consistent 210). Something is off in the calibration. But what's curious is if the ECU was also reading 210-220, the primary fan would kick on, which is not happening... I am stumped.

**Scottydoggs** · 03-02-2014

ditch that 160 t stat for starters, put the 195 back in, even if your modded. the car wants to run at 210. thats why even with a 160 it gets to 210 still. unless your fans have been tuned to come on sooner theres no benefit, if you do all the tuning and crap for the fans, theres still no benefit. the engine runs its best at 210 deg's.

unplug the temp sensor the fans should come on. we've seen guys buy brand new temp sensors and they fail right out of the box. 2 and 3 in a row too. its pretty sad really. parts wise.

**97AutoXVette** · 03-02-2014

Yepp, understood. I am thinking that the temp sensor is just wack. I did unplug it and the fans kicked on which is comforting in case I think I am getting too hot, I have a backup plan. Wonder if there is a temp sensor to go with that can work right the first time! Maybe I will go pull a stock one out of a car in the junkyard nearby...