donbrew

And your next question:

Delfuegosr

Thanks donbrew! Just what I needed for my next phase of troubleshooting. I can see by design that yanking the wires removing the air filter housing over the years may cause problems.

Oldblue

Shouldn't be yanking the wires, should be disconnecting the harness connection
But on mine the wire is alittle stressed


Here's a link to a replacement pigtail

Delfuegosr

I like the K&N setup! Here's where I'm at. I need to check the continuity at the ECM plug to see if the AIT Tan wires are bad at the ECM connector, but it need a pin location map Anybody have that? Im not getting any reading at the connector or when i back probed the 2 tan wire looking for 5.0V signal. Got signal on MAF Yellow wire and 12V on pnk/blk wire... frustating... The wiring is original and there are no visible breaks in the ttan wires in the harness.

It is the connector diagram for the PCM connector C2 that i am looking for. Thanks!

donbrew

Tan is low ref/grnd, it would be bad to get a signal.

Delfuegosr

So the tan wire to pin D (AIT low reference) on the MAF connector, with the key on, engine not running should be 0 V, and the other tan wire (AIT signal) on pin E on the connector should have @ 5 V. I am getting nothing there. I back probed the MAF connector and got the same results. Found the IAT signal wire on the PCM C2 connector and back probed it with the key on and got 0 V. Bad computer? I am getting a 5 V signal for the MAF pin A from the computer. arrggghhh!

donbrew

No. It's a digital thing. Both tan wires are the same, but they connect to the logic chip at different points. Then the digital magic makes something out of it.

Delfuegosr

So should I ever see a 5 V signal on either of the tan wires with the key on ACC? Maybe I'm not asking the right questions...

Again, I really appreciate all the help. I'm not familiar at all with the HHR or the 2.2L eco motor

donbrew

It's not the motor or the car you need to understand, it's digital electronics. I don't know enough to teach anyone.