2003 2500 silverado code P1516 TAC Module

[Greenprecision]

So this is where I stand on my 2003 Chevy 2500HD 6.0L gas... I do not have a code reader but when I have got the codes read it has been throttle position mismatch(this is the weakest link in my journey on fixing the issue) I bought this truck last summer from a ford dealer. It had worked for a month before i started getting issues, it started off as random times under acceleration or deceleration or even when cruise control was on, someone had already replaced the connector end to the throttle body so I then replaced the original throttle body itself, this did not work either. So i took it to the GM dealer to have the software flashed $75 for that and it was done. That lasted for 300 miles, so i then switched the foot pedal out with another pedal and go nowhere, went back to the original pedal, I rewired with all new pins and new connector direct wires from the TAC module to the throttle body still did not work but now seems like heavy acceleration(Load). I then spliced in a ground coming from TAC module to frame ground with same results onder Load it goes into reduced engine power. Last thing I did was put a "new" TAC module on and it is still going into Reduced engine power under load when engine is warm.... about to completely set this on fire... last thing i am going to try is another new Throttle body and wire harness from foot pedal to TAC module. one other thing might be the mass flow as well. any one have any ideas i feel like I have touched every inch of the issues with the throttle body with no success

[rond201]

New throttle body fixed my problem. GM should have recalled this long ago. The new issues with the switch shutting off is no worse than no power in traffic at 65 mph..............

[j cAT]

the problem is with the TAC which is not replaceable . the throttle body need be replaced as a complete assy. also many have had issues with defective throttle body assemblies even GM dealership installed units !!!!!

the TSB was corroded connectors @the TAC ..fact is the TAC are defective.

never use any carb cleaner anywhere on these engines !!!!

good luck .

[Greenprecision]

http://youtu.be/RPIujwkqfLo

Here's the YouTube video of what my throttle body is doing to me with high speed camera

[j cAT]

Originally Posted by Greenprecision

http://youtu.be/RPIujwkqfLo

Here's the YouTube video of what my throttle body is doing to me with high speed camera

what company made this replacement throttle body assy ?

where did you buy this ?

[Greenprecision]

NAPA, Don't remember brand off the top of my head

[Greenprecision]

I am going to a local car/truck salvage place and taking a known good throttle body off of running 6.0L and see if I get the same results. I am curious with the way the throttle body works if the spike in voltage for opening the throttle that far is inducting into the sensing wires and making this happen... but I can not be the only one that will happen to

[j cAT]

Originally Posted by Greenprecision

NAPA, Don't remember brand off the top of my head

should bring it back . many are defective clones.

ya scrap yard is a good idea. get OEM part.

[Greenprecision]

so very angry! My brother owns a couple NAPA's and his part was defective and then Junkyard one off of an 05 6.0L full of carbon I had to clean out works like a top and didn't screw up no matter what throttle position I put at it hot cold and anything in between.... I hope never have to revisit this agonizing experience and 9 months of frustrations.

[j cAT]

Originally Posted by Greenprecision

so very angry! My brother owns a couple NAPA's and his part was defective and then Junkyard one off of an 05 6.0L full of carbon I had to clean out works like a top and didn't screw up no matter what throttle position I put at it hot cold and anything in between.... I hope never have to revisit this agonizing experience and 9 months of frustrations.

so it looks like you did the correct thing and came here to get your vehicle fixed. good luck with your repair.

any time you need to repair electrical/electronic parts best check with the forums and see what others have to say.

My guess is the part you got from NAPA was cheaper. sometimes you can get to pay much more in the end...