i have 88 f150 5.0 aod,been trying to cure high idle so i tested iac like chilton says i think key off disc iac check res should be 7-13 ohm. i have old anolog meter and touched across both pins on iac on x10 pegged it on and x1k pegged it also just like if i touched leads together does this mean its bad or am i testin wrong?? i read about testing tps and i guess im not under standing, it says with ignition F,disconect the tps connector. measure resistance between senor connector terminals SIG RTN and tp. if res readings are about equal to the values in the tables sensor is ok. i wish this had a pic of which terminals to test i dont know what ignt f is or which is SIG RTN and can this be done with an anolog meter thanks cj

 

Analog meter should work best for TPS test.

Let me grab you link.

https://www.ford-trucks.com/article/..._code_124.html

Just have to set it on the hood next to the window so you can watch the meter.

I think analog would work best for TPS check. The other check i'm unsure.

Basically you connect the meter, and press the gas pedal to check for a steady rise in resistance.
Flat spots will hold a continuus or a lowering of the resistance in the TPS.
A TPS is basically a potenteometer with a spring.