Still having issues. Went with a LS2 throttle body. Now it'll start every time, but the peddle is dead until I delete the 1518 code.

 

Do I need to take truck to dealer and have them sync peddle to throttle body?

 

No, there is nothing to sync.

Did you ever test with another TAC module? My theory is that the TAC module is resetting during powerup, so that the PCM powers up first and detects a loss of communication(1518)with the TAC module. The 5V regulator in the TAC module can trigger a reset of the microcontroller under certain conditions such as the output dropping below a given value, even momentarily. Let me know if a different TAC module makes a difference. We can do a swap for a modified X-Link that may help if this is the case.

 

I haven't tried a new tac module. Since mine is a 03', and being the first year for the electronic TB, would a newer, more up to date TB work better? Idk if there is a difference.

 

Any 2003-2005 TAC module should work on your truck if you can swap with someone just to test.

 

Is the TAC module sensitive with the 90mm TB's? I just dont get why it works fine when I hook back up my factory 78mm. It won't throw any codes. Only when I hook up the 90mm. Could it still be bad even though it works good with the factory?

 

For a start, the 78mm TB has 2 completely separate sensor circuits each with its own 5V and ground. The 2 sensor circuits in the 90mm share a single 5V and ground circuit.

Depending on the design of the trigger circuit, splicing into a TPS circuit for a trigger can change things up again. P1518 is common with these.

 

I dont have any friends that drive a 2003-2007 silverado. i at have to just buys new TAC.

 

I disconnected the trigger switch. I had someone install my nitrous system. Looks like they just stripped some of the coating on the signal wire and soldered the trigger wire to it, luckly the factory signal wire was never cut

 

2003-2005, 2006-2007 are different