On my third air temp sensor, please help!
 

Air temperature sensor issues started as soon as I switch to efi. My first sensor(haltech brand) would read high (cold day after sitting 24+ hours on a cold michigan day and read 80F) so got a new one (summit racing) and blamed the lack of a heat shell for the first ones demise. The summit one worked good for a year, but I recently switched for supercharged to turbo, and while tuning I notice the a solid -40F (open signal I'm guessing as that what is shows when nothing is plugged in.) I put the old "high" one back on and got a temp, and put a new connector on that a had ordered when the first sensor went bad, and got the same results. My third sensor is a Autozone old school GM (metal cage instead of plastic) and I would like it to last. Any ideas on what I'm doing wrong?

1988 13BT ported, E6X, HKS turbo kit (log manifold, to4e, Jay-pro Intake, DYI front mount inter cooler, NOS wet kit (not in use until can tune on dyno next spring)

pics
 

https://www.rx7club.com/attachment.p...1&d=1225580380
From left to right (had manufactures wrong in post) The "high" senor made by delphi, the -40 sensor with no markings, and the old school gm from advanced autoparts

When its reading 80F on a cold day is that before you even turn it over? Cause soon as some heat gets in the engine its going to heatsoak the piping and the sensor.

Where are you placing the sensor? does the sensor go bad with no apparent cause to it? or does it coincide with any sort of event? Ive never seen one of those sensor go bad just for the heck of it, usually its due to something.

Where did you locate your NOS fogger? does the sensor get sprayed by it or is it located before in the intercooler tract? If you have sprayed the NOS but the sensor is not in front of it, have you ever gotten backfires or bangs while run it?

The first sensor was over my exhaust, and I believe heat damged it. The 80F after not running for more than a day, was a true bad reading. It was livable as the whole graph seemed to shift up. The dead one did run with nitrous on my supercharger, and yes I had a nitrous backfire once but it worked afterwords. Yesterday when I started tuning the temp sensor worked (maybe intermetant), at the end of the day I did some data logging and thats when I noticed it was dead. It looks fine, the two wires seem to still be in good shape, but no signal.

I convinced I'm the cause, weather it's running too high of intake temps, under hood temps, or something. My wiring is per the haltech diagram, and my connector is brand new. I plan on using nitrous in the future, do I need a special sensor? I barely picked up any temp drops when I sprayed in the past, but would like to spray before the temp sensor as to pick up any drop.

See the temp sensor on the right side of the turbo bonnet
https://www.rx7club.com/attachment.p...1&d=1225630853

I would probably move to the coolant sensor as its a protected type. You won't see the instantaneous temperature changes that you would see with the open element type but it will be more robust. If your sensor is above the exhaust it should have been heat shielded anyway. Spraying before the the sensor I believe is a bad idea as the temperature changes are going to be artificially lower than the rest of the intake charge. I would think looking at your EGT's would be a better choice. It would also show you whether you are allowing more cooling on one chamber over the other.

Fritts has a point, the Coolant sensor may be more durable for you in this sort of hostile conditions, since its brass all around.

And the resistance measurement is identical in both units, might be worth trying it.