Probably in the wiring.

 

been trying to check that, you think between the tps and pcm

 

Yeah. Are you getting 5v? One should be ground and the last one shouldn't go to ground if you ohm it.

 

when you say tps, you are refering to the accelerator pedal correct? Some code readers will call the accelerator pedal sensor a throttle position sensor. The code definition I have for p0122 is accelerator pedal sensor circuit low input.

Possible causes for p0122 are:
Damaged accelerator pedal assembly
AP (accelerator pedal) sensor not installed properly
Faulty AP sensor
Grounded wiring harness
Faulty PCM
Being a mechanic, I do see some bad, new parts so don't rule that out.

First thing to do is make sure you installed it correctly. Second is to check the wire harness plug at the AP for loose or damaged terminals. If all looks good there, you will need a code reader or scanner to read data PID's. A couple of easy things to check are to make sure the brown/white wire at the AP has a 5v ref with ignition on, engine off and the yellow/white wire for a good ground. With the AP wiring connected, and ignition on, engine off, black lead of your volt meter to a good ground, probe the grey/white wire. Watch the volt meter reading as you slowly press the AP. If the voltage changes as the AP position changes, the AP sensor is good. You will need some way to read PCM PID's (realtime data values) to make sure the PCM is getting a good voltage value from the AP.

Hope this helps and you find your problem. If you have any questions, I will answer them the best I can.

 

it has new pedal assembly voltage looks good, took it out and drove it with scanner graphing output of pedal sensor and when it cuts out singal does also, i'm like you i have seen bad parts, i just wish it would either be bad or good not intermittent. I'm still leaning toward pcm just hate to spend money i dont need to. Also wiggling wires while running mid throttle does not effect it.
thanks for the help

 

No sure about your truck (you didn't say Early/Late 99), but I would have a look at the OD Button wires at the bottom of that stalk where they commonly chafe through. That circuit can be on a shared fuse with the TPS and, when blown, prevents the TPS from getting Any voltage. Maybe partially shorted is drawing-down the line?

A Free Fix anyway so it might be worth a look...

 

If your scanner will graph the signal of the AP sensor, then I would say you don't have a bad PCM because the signal goes from the sensor to the PCM and then to the scanner. With you saying you did a wiggle test while at half throttle, does the truck cut out at half throttle? The PCM is showing the code because it sees a momentary loss of signal. You should be able to take the new sensor back and tell them that it's not working properly and exchange it. I would give that a try before you buy a PCM.

 

put a new pedal assembly from ford on seems to have fixed it, i did have a cps code today in the rain, is there anything to the wiper motor effecting cps like i read on here, if so should i go back to black cps like it said

 

I have personally never had a problem with either color cps but I have seen a lot of people on here and other sites that have. If rain is effecting your cps, put some dielectric grease in the wire plug. That will stop the moisture from getting inside to the terminals.

 

It actually has to do with the interference with the wiper motor itself, not water I don't think and it was only the Black CPS that showed those symptoms (the Grey was the "cure").

http://www.powerstroke.org/forum/99-03-7-3-motor-problems/13006-stumbles-when-rains.html