Another simple question.

[Maetrix66]

Okay, this is an easy one for someone whos been down this road.

My 3100 runs in my fiero now, and I am able to drive it in and out of the garage. the check engien light is on, so I took the scan tool and pulled the code. It is for the coolant temp sensor, which isn't connected. It's a one wire sensor on the 3.1, but a 2 wire sensor on the 3100, which everyone knows. My question is this, I have a 3100 coolant temp sensor. can I get away with just connecting the signal wire to the green coolant temp sensor wire on the 3.1 harness, or do I have to ground the black wire to the block as well? I am trying to use the 3100 sensor to avoid using a helicoil to install the 3.1 sensor.

Thanks in advance for the help!

Chris

[Guest]

The 3.1 and 3100 (depending on the year) both use 2 wire coolant sensors for the ECM. The single green wire coolant sensor is for the gauge or light.

Both engine have this coolant sensor located in the T-stat housing and use the same colours (black and yellow) for the signal to the ECM.

To avoid drilling and tapping the head on the 3100 (sounds like you have a '96 or newer 3100), you can use a 3 wire coolant sensor from a '92 2.2L Cav (just one example), the 3 wires are signal ground, signal (to ECM) and signal (to gauge), I can post a link to more detailed info in a bit.

[Maetrix66]

thanks

Thanks, that will help alot. I have a plug in the rear head for the old style sensor, but I couldn't get it out, so I was looking for another alternative. Thanks!

[Guest]

Here's the link I was talking about:

http://www.domesticcrew.com/660board/viewtopic.php?t=33

[Maetrix66]

Thanks

Thanks, this helps alot.