if i am reading 5 volts at my harness does that mean that everything is ok with my wiring, or could there still be a problem?

i've tried two different IAT sensors and and im still having the same prob with both. (runs great until it warms up, then throws a code 23 and and dies(with the sensor unplugged),and doesnt want to run at all with the sensor plugged in at startup))


i know that the IAT is critical to my engine seeing as how i have a 93 which uses speed density.

if the speed density system uses the IAT all the time how come my car runs fine until it switches to closed loop (sensor unplugged)?


believe me ive searched and cant find the info im looking for.

 

This will directly applly to you as it's from a 93 service manual:

http://home.comcast.net/~fastbird/Tr...ds/dtc23p1.jpg
http://home.comcast.net/~fastbird/Tr...Aids/dtc23.jpg

Just read them in order, and follow the diagnostic chart and that should help you immensely.

 

thanks Fastbird93 that helps out alot!

I also found some more troubleshooting info on here after some more searching so i should be able to find my problem.

I am still curious as to why my car runs fine until it switches to closed loop, if the speed density system uses the IAT from startup.

i would think there could be another problem other than the IAT that occurs only in closed loop but i remember before the rebuild i forgot to plug the IAT back in one time and the car ran fine until it switched to closed loop. i then simply plugged it back in and the car went back to normal.

????

 

i did some tests and would like some help diagnosing my problem. i think its a bad pcm, unless i have a damaged IAT wire that i cant see.

test 1- pcm unplugged and IAT sensor unplugged. I probe the two ends of the IAT pigtail and get an OL reading. by doing this i concluded the wires are not shorted together somewhere.

can anyone tell me or show me a diagram of which pcm connector the other end of the IAT sensor goes to on a 93. my wires are dirty and several of the colors look the same.
i checked shoebox's site but i couldnt find what i was looking for.


also, does anyone have any insight to my previous question?

 

C22 at the ECM for the tan wire to the IAT. The IAT black wire joins to other grounds and returns to the ECM on B3.

 

thanks

 

i just checked the resistance from one end of the IAT sensor wires to the other.

touching the probes together i get .5 ohms

the tan from end to end reads .8 ohms - .5 ohms= .3 ohms

the black from end to end reads .8 ohms - .5 ohms= .3 ohms

isnt .3 ohms of resistance about normal? or do i need to replace these wires?

if the wires are ok and the sensor checks out that only leaves the pcm. correct?

 

.3 is not much. Since they both read the same, I would say they are probably ok. Do you have a scanner to monitor the IAT reading?

 

no, i dont have any type of scan equip. i probably should invest in some soon though.