Reduced engine power

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I am having a problem with reduced engine power. I replaced MAF MAP and throttle body I’ve chased every ground I could it’s throwing a po103 all the time and whenever it does reduced engine power it throws a po068 any solution ideas?
 

ORVietVet

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P0068-TPS and MAF/MAP problems communicating.

Welcome to the forum from Oregon.

I am a smart ass, so here goes: Are you of the opinion that each and every GMT800 made between 1999 and 2006 are EXACTLY the same? Since they are NOT, I ask this?

What vehicle info are we talking about? OR.....is it a secret?
 

ORVietVet

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Also, you replaced the throttle body and should I assume it came with a new TPS? When a TPS is replaced, GM recommends replacing the connector to it as well.
 
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P0068-TPS and MAF/MAP problems communicating.

Welcome to the forum from Oregon.

I am a smart ass, so here goes: Are you of the opinion that each and every GMT800 made between 1999 and 2006 are EXACTLY the same? Since they are NOT, I ask this?

What vehicle info are we talking about? OR.....is it a secret?
A 2006 Silverado with the 5.3 I know there not all the same haha but I know they share most of the same hardware
 

ORVietVet

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A 2006 Silverado with the 5.3 I know there not all the same haha but I know they share most of the same hardware
Key word there is "most". Generalized vehicle info here or in any other thread can cause problems or create going down a hole and waste time.

Of all the parts that you replaced, did you check or replace any connectors and did you check condition of connectors at the PCM?

Did the throttle body come with a new TPS?
 

stutaeng

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I've never had this issue myself (except when reflashing a tune using HP Tuners, but deleting the code is all it takes).

There's a TSB on replacing the throttle body pigtail, which I think is where the problem lies. I believe the wires start breaking down, even though they look fine on the insulation or something like that.

What I've recommended to folks on the forums is, finding a wiring diagram, and backprobing the throttle body and the corresponding wires at the ECU, then running jumper test cables temporarily. The temporary leads will prevent signal loss between those two parts, because you've provided an alternate electrical path.

Drive it around and if the problem is resolved you know where the problem is. You can either replace the pigtail and hopefully the wiring issue is there, or simply run a new set of wires, with wire loom, you probably won't even know it.
 
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Also, you replaced the throttle body and should I assume it came with a new TPS? When a TPS is replaced, GM recommends replacing the connector to it as well.
Yes I replaced the TPS I did not replace the connecter I couldn’t really find where to buy one exactly except for eBay but to replace the connecter would I just cut the old one and solder it together?
 
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I've never had this issue myself (except when reflashing a tune using HP Tuners, but deleting the code is all it takes).

There's a TSB on replacing the throttle body pigtail, which I think is where the problem lies. I believe the wires start breaking down, even though they look fine on the insulation or something like that.

What I've recommended to folks on the forums is, finding a wiring diagram, and backprobing the throttle body and the corresponding wires at the ECU, then running jumper test cables temporarily. The temporary leads will prevent signal loss between those two parts, because you've provided an alternate electrical path.

Drive it around and if the problem is resolved you know where the problem is. You can either replace the pigtail and hopefully the wiring issue is there, or simply run a new set of wires, with wire loom, you probably won't even know it.
Thanks I might try this tomorrow yes I clear the code to get it running again lol
 
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Key word there is "most". Generalized vehicle info here or in any other thread can cause problems or create going down a hole and waste time.

Of all the parts that you replaced, did you check or replace any connectors and did you check condition of connectors at the PCM?

Did the throttle body come with a new TPS?
I did not check any of the connectors at the pcm is thst located next to the firewall behind the engine?
 

stutaeng

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The ECM (or PCM) is located on the front driver's side, between rhe fender well and the frint clip...it has a plastic cover that literally just snaps on.
 

ORVietVet

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The PCM is below the battery tray and to the inside toward the engine, directly below the engine side edge of the battery tray. Just another way to describe what @stutaeng said.


Connector looks like this.

Connector part #'s: AC Delco-PT2319, Standard- S619 or HP4440 and genuine GM part # at the dealer would be starts with the same 8898-first 4 numbers and then multiple finishing 4 numbers: 8301, 8144, 8107. 7969
 
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The PCM is below the battery tray and to the inside toward the engine, directly below the engine side edge of the battery tray. Just another way to describe what @stutaeng said.


Connector looks like this.

Connector part #'s: AC Delco-PT2319, Standard- S619 or HP4440 and genuine GM part # at the dealer would be starts with the same 8898-first 4 numbers and then multiple finishing 4 numbers: 8301, 8144, 8107. 7969
The only thing that comes up for this is a 3 wire mine has 8 wires I’m pretty sure
 

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