Ok the current temperature is 14 Degrees. Truck sat outside for 8hours in the cold. The only mods are Radix, 3.1 pulley, LT, Exhaust, Off road Y pipe, cold air intake, black bear tune.

To get to the story I try to start the engine and it ran very funny real rough and the engines computer said reduce engine power. I turned it off for a sec and cranked it again same thing. I then opened the hood nothing looks out of ordinary. I try to crank it and it starts fine check engine light on.

I get home and check codes.
P1516 No description found in DTC database
P2108 Throttle Actuator Control module perf
U0107 Lost Communication with throttle actuator control module

Any clues whats wrong.

 

I had the same problem once. I would push the throttle and my RPMs wouldnt go up. it ended up being a grounding issue. i just figured id throw it out there cause the problem sounded the same.

 

90MM TB or stock?

 

mine did that due to unmetered air going passed the MAF

 

mine did that when my throttle body was dirty

 

As has already been mentioned, it could be several issues, but being that it is so cold in your area, the throttle blade could have just stuck. The way the TPS works on the ETC equipped vehicles, it is basically a dual TPS and one side reads the actual throttle position, while the other side reads the commanded throttle position and if the variance is too great it will throw it into REP. Of course you may say that you haven't hit the accelerator peddle yet, but when you 1st turn the key on, the throttle blade opens and closes to perform a self diagnostic and if the blade was stuck it would fail.

P1516 - Throttle Actuator Control (TAC) Module Throttle Actuator Position Performance
Circuit Description
The commanded throttle position is compared to the actual throttle position based on accelerator pedal position (APP) and possibly other limiting factors. Both values should be within a calibrated range of each other. The engine control module (ECM) continuously monitors the commanded and actual throttle positions. This DTC sets if the values are greater than the calibrated range.

Diagnostic Aids
The throttle valve are spring loaded to a slightly open position. The throttle valve should be open approximately 20-25 percent. This is referred to as the rest position. The throttle valve should not be completely closed nor should they be open any more than the specified amount. The throttle valve should move open and to the closed position without binding under the normal spring pressure. The throttle should NOT be free to move open or closed WITHOUT spring pressure. Replace the throttle body if any of these conditions are found.

As far as the other codes are concerned, they could be caused by:
The Throttle Actuator Control (TAC) / throttle body type trouble codes may be caused by a loose wiring crimp at the throttle body connector, or a broken throttle body circuit.

Inspect all related throttle body terminals for a loose wiring crimp. The loose crimp may be difficult to find, and the poor connection will be between the terminal and the copper strands of the wire. Wiggle test the individual throttle body circuits to see if the concern can be duplicated.

Inspect the related circuits for broken wires inside the insulation. The outer wire insulation may look fine, but the internal copper strands may be partially broken. Breaks in the wires usually occur within 1 to 4 inches of the throttle body connector. Wiggle testing may also induce a trouble code to set.

On C/K trucks complete SI procedures for voltage drop on grounds G103 and G104. Grounds G103 or G104 may be loose or corroded.

If a terminal crimp or a broken wire has been found, repair or replace only the circuits involved. There is a throttle body pigtail connector available through GMSPO, but installing this pigtail connector may cause other intermittent TAC module/TP codes at a later date.

 

Mine did the same thing on an 03 1500 I had and it was the TPS, I just had to replace it with a new TB.

 

P1516- TP does not correlate with commanded TP(pedal position): check for a sticky throttle blade, low system voltage, ground or wiring issues.

P2108- This is the first time I have seen anyone have this pop up:

DTC P2108

Circuit Description

The throttle actuator control (TAC) module contains data which is essential for proper TAC system operation. The TAC module continuously tests the integrity of this data. When the TAC module is unable to write or read data to and from random access memory (RAM), or the TAC module is unable to correctly read data from the flash memory or an internal TAC module processor fault is detected, this DTC sets.

 

Stock TB

 

Ok. Going to clean the TB. Going to check G103 and G104 if corroded I will replace tighten if needed. Then will move on to checking the wiring. Thanks guys.