Re: Mas airflo low voltage
The Mass Air meter is supplied 12 volts (through a pcm relay) in common with all the fuel injectors, IAC, intake runner control, EGR regulator and a number of other items.
One meter lead goes to ground, one to 12 volts, the other 2 go to the PCM to deliver the signal +/-.
It could be the sensor quality but the same result 3 times tells me you should look at the harness for issues.
Low cost sensors are often test rejects from the same mfger that make good ones.
Don't just jump on a code that refers to the sensor, as the only cause of the problem.
One of the best ways to look at this is with a scanner to look at the live MA data while the engine is running.
The air meter is a bridge circuit configured like a diamond with resistances in each leg. Three resistances are fixed, one is a heated resistance element that is cooled by air passing through and changes it's resistance as the output signal to the PCM.
A voltmeter test may be helpfull in finding the low voltage condition.
The PCM monitors the sensor for low and high voltage out of limits and sets the code when found out of limits.
Likely more than you wanted to know but someone has to know a little about what their looking for.
For test limits, look up the 'FORD' 102 code definition in 'full' and not just run with the mention of mass Air sensor. You get fooled often, that way.