87BlazinIroc

Hey im kinda new to TGO but the other day I was changing my plug wires and noticed a male 2 pin connector tuck behind the wiring harness , the wire colors are black and what looks like orange w/ black stripe , or tan w/ black stripe , I had this car for about a year now , its a 87 iroc , if that help any, Thanks in advanced

greenyone

iTrader: (1)

picture & location ?

87BlazinIroc

Location is driver side rear of engine near fire wall

greenyone

iTrader: (1)

That goes to an intermediate wire that goes between the harness and the air charge temp sensor located under the rear of the upper plenum.

harness->intermediate wire->air charge temp sensor

Are you throwing a SES code?

87BlazinIroc

I would throw a ses code every once in a while on the highway but as of normal everyday driving, no ses code, I was thinking the ses code that was showing was the maf , once the ignition is of and u start the car again no ses code

87BlazinIroc

I traced the iat wire from under the plenum to a plug on the passenger side that goes into the harness, does the connector plug that I previously talked about plug into another wiring harness from there ?

greenyone

iTrader: (1)

On mine (1991 speed density LB9) that lead with the 2 prong male connector coming from the main harness on the rear drivers side of the engine plugs into a wire like this one: [see image in link]

http://i00.i.aliimg.com/wsphoto/v2/948310926/longyue-factory-sale-20pcs-86-92-TPI-Camaro-Firebird-Corvette-Intake-Air-Temp-Sensor-Wiring-Harness.jpg

that small harness plugs into the main harness and then up to the air charge sensor/MAT sensor under the plenum. I'm guessing GM did this because it's too hard to get at the sensor to unplug it under the plenum. So they added an intermediate harness that can be unplugged at the main harness. This way when you pull the plenum to service anything that would require it's removal, that little intermediate harness can come off with the plenum.

Maybe your car is slightly different if you have an earlier TPI that is not "speed density" that uses the MAF in place of the later MAP sensor.

If your car is a MAF (mass air flow) car it may be different. That's also assuming that your car is not a a hodge podge mix of sensors/harness and ECM's from different year cars. Maybe somebody else can chime in here that has a MAF TPI car for comparison.

87BlazinIroc

Yes mine is maf and I have the same mini harness but runs on the passenger side into the main harness, looks exactly the same wire colors but on a different side and the connector from the main wiring harness is female not male , I was trying to figure out did the mini harness have another plug in from that harness that ran from the passenger side to the drivers side

iroc-z383