I have a 2007 Silverado with a 5.8l, It keep coming up with engine code P2138 and the truck just about dies, it says "engine power reduced". In the last 3 months I have changed the throttle pos. sensor and the Accelerator Position sensor(gas pedal). Now it doing it again, anyone have any ideas???? Thank You, Debbie

 

Hope this helps you out.

P2138 Possible Causes

What does this mean?

• Accelerator Pedal Position Sensor harness is open or shorted
• Accelerator Pedal Position Sensor circuit poor electrical connection
• Faulty Accelerator Pedal Position Sensor
• Faulty Electric Throttle Control Actuator

 

1) 2007 was a design change year - is it Silverado or a Silverado classic? The difference is the headlights are divided vertically by a chrome strip off the grill on the classic whereas the newer style has a 1 piece headlight housing. You can also tell by the tailgate - the classic has a “Chevrolet” decal and the newer style has a bow tie.

2) I’m guessing 5.8 is a typo? It should be either a 4.8 or a 5.3.

3) GM issued a service bulletin for P2138 and that it could be caused by water intrusion into the primary instrument panel connectors, located in the driver side footwell. Disconnect the battery and unhook the connectors in this area to inspect for corrosion. I can’t tell you exactly which connectors you need to look at, but if you trace the harness from the accelerator pedal, it should lead to them.

 

Usually when a system goes into "Limp mode" there is a power reduction to prevent further damage until the problem is corrected.
Some conditions will reset if the ignition is turned off others will not. If the suggested fix is as stated in an earlier post , by all means check it out. If not, it may require some checking with a capable scan tool and wiring diagram.

 

Did you check your ground wires? Also, depending on where you live, check the wire connectors and harness for cheese.