"Engine performance decreased"

[Mainecobra]

"Reduced engine power" code P2138!!!! Update

Ok this is happening out of no where. I have a 2006 lbz fully built socal motor built big dipper trans everythind deleted tuned by moonshine tunes ( tony) and a ton more. Anyways truck has run perfect for a long time with zero issues. I went to camp for a week we had a bad storm on the lake started the truck up the next day drove it for about 30 mins that the " reduced engine power" display came on. This truck has never ever displayed this. There is no CEL just this display on tue DIC. Went home unhooked the negative waited about 10 mins attached restarted truck and gone. Never came back on for about 2 days of driving. Now 1 week later im driving the truck for about 2 hours and out of no where engine power decreased comes on again. Then shut the truck off to eat dinner for about 1hr and it went away. Then a few minutes driving down the road it comes back on. Every gauge is perfect. Only thing that the few times its done this ill have decreased theottle response. Im stumped on this one. Also changed the water seperator/ fuel filter air dogs about 1000 miles ago. This came out of no where and wondering if anyone has had similar issues.

 

[clrussell]

Throttle pedal sensor very possibly.. You need to read codes to be able to get more info.


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[Mainecobra]

No codes are being thrown. Its just displaying " decreased engine power" onnthe DIC cluster. There is no check engine light at all.

 

[Mainecobra]

And when the " engine power decreased" was on today on the 2hr ride home it drove fine. I was trying to get on it a bit to see if i noticed a power loss and it did feel like it wasnt pulling as hard. But no trans limping, no engine not accelerating. Just trying to figure out what the hell it causing the diplay to trigger.

 

[gmduramax]

Maf?

 

[Mainecobra]

I know I was thinking MAF also. Which i will take out tommorow and clean. But i just find it odd for all of a sudden the MAF to act up for no reason.

 

[gmduramax]

I've been through 3 in 4 years

 

[Mainecobra]

Ok well maybe thats the culprit. I hate playing the guessing game though. I hate replacing something if its not causing the problem. Have you figured out why your truck is going through MAF's so often??

 

[gmduramax]

Nope lol keep getting it warrentied

 

[NC-smokinlmm]

There's a code if it displays that message. You need a tech 2 or efi live to pull it out of the ecu. Not all scanners are created equally...

 

[TheBac]

Had it been raining/wet just before or when you were seeing the message the second time??

x2 on getting a Tech2 or EFI to help diagnose it.

 

[Mainecobra]

No it was a beautiful day. So next day after sitting over night code goes away and now hast came up all day.

 

[Mainecobra]

So went off then came back on. If the truck sits for a bit it will turn off than pop back on again after a 20 min ride. Display stayed on so i ran inside and grabed my autocal and it read the code p2138. Assuming this is the throttle position sensor?

 

[Lparrill]

So went off then came back on. If the truck sits for a bit it will turn off than pop back on again after a 20 min ride. Display stayed on so i ran inside and grabed my autocal and it read the code p2138. Assuming this is the throttle position sensor?

Yes, do you have a lock up box? Bet theres a loose wire somewhere

 

[Mainecobra]

Lock up box? Elaborate on this please. Do u mean front locker? So i started really thinking about when this started. I was at the lake and we had easentially a hurricane on the lake. Crazy winds and crazy rain. Windering if water got into the ecm so how? It never did this for years not even once and all started after that storm. Maybe a coincidence but it does seem odd. Yea i agree it has to be a loose wire somewhere. I removed the connector from the accelerator pedal and sprayed it down with electric parts cleaner.

 

[clrussell]

Lock up box? Elaborate on this please. Do u mean front locker? So i started really thinking about when this started. I was at the lake and we had easentially a hurricane on the lake. Crazy winds and crazy rain. Windering if water got into the ecm so how? It never did this for years not even once and all started after that storm. Maybe a coincidence but it does seem odd. Yea i agree it has to be a loose wire somewhere. I removed the connector from the accelerator pedal and sprayed it down with electric parts cleaner.

By lockup box he is meaning a torque converter lockup box.


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[Mainecobra]

Or do u mean line lock? No i dont have like lock and i do have a locker for the eaton in the front diff but that switch is in the glove box

 

[Mainecobra]

Ahh gotcha. No i dont have a lock up box. Im really thinking its a connection issue or maybe its just the accelerator pedal sensor. Just seems such a odd sensor to go all of a sudden. Its such a pain chasing electrical issues.

 

[Mainecobra]

Had it been raining/wet just before or when you were seeing the message the second time??

x2 on getting a Tech2 or EFI to help diagnose it.

It all started after the crazy hurricane like rain storm on the lake my truck was parked bedind the house. The second time perfect day 80 degrees no rain.

Yea grabbed my efi autocal and showed the code ecm p2138

 

[Mainecobra]

Has anyone replaced thier pedal assembly and sensor and it actually solved the issue with the display engine power reduced code p2138?