AFM Problem Code 24 and 31

[Afunk]

Hey,

Recently, my car suddenly developed a horrible idle and inability to rev. My first thought was the AFM and after checking the codes and getting 24 and 31 I assumed I was correct.

I then got another working AFM and the same exact thing happened.

I've tested continuity between either ends on the wiring harness and all 5 wires going between the AFM and ECU have continuity.

Since code 24 and 31 and seperate systems, it could have also been a bad positive or ground. I checked at the AFM end on the wiring harness with the key in the "on" position and I got 5 volts which is what it should be.

I also have a ground strap on the AFM.

I guess my next step is to get another working ECU.

If there is anything anyone could suggest or add, I'd appreciate it.

Thanks,

Alex

 

[Afunk]

helpppp meee

 

[BTZ]

just a note when i was messing around with my o2 sensor, when i unpluged it and ran the car it threw 24 and 31

 

[Afunk]

I appreciate the replys guys. I have not yet tested the resistances in the air flow meters themselves as the other AFM I tried was supposedly pulled off a running car. The HAC is something I should test, I will get on that.

Continuity was checked by unplugging both ends of the wiring harness and looking up the pre 89 ECU pinout and connecting the ends to a multimeter that has a "beep" continuity function, basically very low resistance so that is good.

I don't think it is the O2 sensor because even if the O2 sensor were bad/not plugged in, it would still be able to run just under default non-optimal settings and open loop/ WOT conditions would not suffer. In the case of my car, the engine can hardly idle and sounds like it has bad misfires and will not rev and if it does will have a second or two delay.