TPS or APPS?
 

Is this the same thing? I've got a 1693 code cuz of some dead pedal issues and went to Advance, it came up as 0121 which said it was TPS. So is a TPS the same as the APPS or is that something different?

On an '01 you have an APPS. If a reset doesn't help your problem, you can get an aftermarket unit here:
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yes there are the same thing. try resetting it. if that dont work then it needs replaced

Reset what I got U 0121 today. Help please!! Can't seem to find the meaning of the code on the website.

Her's the info on your APPS. https://www.dieselbombers.com/24-val...tomy-apps.html

U0121, No communication with the ABS (CAN)

Might want to check the connection to the ABS module.

ABS module, is this for the obvious having to do with brakes, or is it something else?