Dreaded reduced power mode. argggggggggg

[Eldiablo]

Okay I have an 05 tahoe 315,000 miles. Just got the reduced engine power message. So I am going through all that I have read. On the back of the motor I have the ground on the driver side that goes with the silver one. I beleive its for the ac compressor. On the pasenger side I have nothing. I need to know what is suposed to be grounded there so I can hunt it down. So far I have put a new throttle body, change the the throttle computer. Did the ground improvement but still get this thing. My battery while its running does not go below 14.6 12.4 when its turned off. 55 lbs fuel pressure. I am beating my head. I put new injectors, gaskets, this is driving me crazy. And its the old ladys tahoe, and she is driving my truck. She is ******* vehicles. This thing has been bullet proof for so long. I mean has the original transmission in it. Hlep please??????????????????????????????????????????????????????

Ryan

also I really could use a schematic showing me what grounds go where and what they are attacked to???

 

[Fless]

Post up the codes you're getting; that might help us help you.

I've attached a grounds diagram from the uptfitter's guide.

 

[Eldiablo]

typical 1516 code I beleive

 

[Eldiablo]

Post up the codes you're getting; that might help us help you.

I've attached a grounds diagram from the uptfitter's guide.

Thank you. One thing that is new. Last night early this morning, when I started it , idled perfect, but right berfore is went crazy, I could hear loud clicking sound, seems like coming from throttle body?

 

[Fless]

Moved you here from the 2021+ section.

 

[Fless]

Based on your stated P1516: with a good scanner compare the throttle position with the pedal position values. There are some good YouTube videos on how to do that.

Also, the wiring from the throttle body has a tendency to break under the wiring insulation. Very carefully inspect the wiring harness from the throttle body back about 6 or 8", looking (feeling) for wire that's compromised under the insulation. You can get a new pigtail for that harness, or repair broken wiring.

 

[strutaeng]

Pop the fuseblock cover and unclip to inspect the terminals/connectors that plug to the actual fuseblock. It's very easy to do this, you'll just have to remove the little corner brace. Have a wiring diagram to pinpoint the wires that go to the throttle body.

Maybe you have corrosion there?

 

[blackelky]

You guys are giving me hope with these high mileage posts...ever had a trans replacement ?

 

[Eldiablo]

Based on your stated P1516: with a good scanner compare the throttle position with the pedal position values. There are some good YouTube videos on how to do that.

Also, the wiring from the throttle body has a tendency to break under the wiring insulation. Very carefully inspect the wiring harness from the throttle body back about 6 or 8", looking (feeling) for wire that's compromised under the insulation. You can get a new pigtail for that harness, or repair broken wiring.

Did I mention I sold tools for 34 years. I have been wanting to get and x tool d7. Havent done it yet, I sure could use it.

 

[Eldiablo]

Did I mention I sold tools for 34 years. I have been wanting to get and x tool d7. Havent done it yet, I sure could use it.

Brand new pig tail. Ive had the harness under the hood completelly apart.