Have a rebuilt motor installed and now getting P102code. Replaced mass air flow sensor and still same issue. Is causing a rough idol. All other sensors were replaced with new ones. New upper intake with new spider injectors. Anyone have any ideas?

 

Sounds like you have a Air Flow restriction somewhere. Have you checked the Air Filter? Another possibility I think that would cause this problem is a bad Catalytic Converter. You do loose engine power. This is just a suggestion but something to check anyway, in my honest opinion.

 

This code would be easiest to diagnose with either a pocket scope or a scan tool that can read live data; however a decent meter can do the trick if you know how to use it.

The MAF sensor generates a frequency dependent on engine speed - lower at idle and higher as engine speed increases. A scan tool will read this as air flow in grams/second and may also display the frequency (depends on tool).

P0102 indicates a low frequency meaning there’s an issue with airflow through the engine (a restriction as Birdman01 suggested), the sensor itself, or the wiring.

On a scan tool, look for 0 g/s at key on engine off, 4-7 g/s at idle (engine warm), and at least 100 g/s at WOT just as the 1-2 up shift occurs.

At the MAF sensor, Key on engine off, look for battery voltage on the pink wire and a bias voltage on the yellow wire. I don’t know what the bias voltage is off hand but it should be reading anywhere from 0.02 to 5 volts.

Check for a good ground on the black/white wire with an incandescent test light.