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I'm getting a code p2138. It's a p2138. 2004 gmc envoy. I…

Customer Question
I'm getting a code...

I'm getting a code p2138

Mechanic's Assistant: Just to clarify, what's the exact code? And have you tried to reset it?

Yes it's a p2138

Mechanic's Assistant: What is the make/model/year of your car?

2004 gmc envoy

Mechanic's Assistant: Are you fixing your Envoy yourself? What have you tried so far?

Yes I changed out the app sensor

Submitted: 2 months ago.Category: GMC
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Answered in 6 minutes by:
5/31/2018
GMC Mechanic: Pete, GMC Mechanic replied 2 months ago
Pete
Pete, GMC Mechanic
Category: GMC
Satisfied Customers: 33,303
Experience: GM training and dealer tech for 14+ years. Diagnostics
Verified

Hi, my name is ***** ***** I will be happy to assist with this today. In some cases, I may need more info to assist better. I apologize for any delay.
I try to be here most weekdays and some weekends. If you respond and I do not respond back right away I will do so as soon as I can.

Since the app sensor was replaced already this can be due to a wiring fault to the app sensor or control unit. The diagnostic test procedure below needs to be followed to then locate which is the case here.

https://www.dropbox.com/s/3w5b4ktabhv04jg/p2138-05-31.png?dl=0

Here is the diagram info on this.

https://www.dropbox.com/s/121m6sz7ggr6hpn/app-05-31.pdf?dl=0

If the computer has to be replaced it will need to be programmed by a dealer in order for it to operate in your vehicle.

If more help is needed, use the reply tab to continue our conversation. If no further assistance is needed, kindly rate my service, your 5-star rating is appreciated ( should be a link to click on here or above). You can rate at any time and we can continue to work on your question as this will not close out your question. I work on delivering the best answer and help here but in some cases, it can be difficult to do without seeing the vehicle.

Thanks, Pete

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Pete, GMC Mechanic
Category: GMC
Satisfied Customers: 33,303
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Experience: GM training and dealer tech for 14+ years. Diagnostics

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