Hi,
I have a Chevy Malibu 2009 that I acquired from a GM dealer. I had a problem this afternoon when I started the car, it felt like the battery was discharged, when I got in the highway and accelerate to incorporate to the traffic it didn't accelerate so I had to pull over right away. Then I noticed the engine was shaking and a lot of noise coming from the engine, I drove to Autozone to get it checked. Codes P1516 and P2101 came up. Any idea how this can be resolved?

Some interwebbing has yielded the following:
OBDII diagnostics. Trouble code definition for code P1516. Causes of error P1516
OBDII diagnostics. Trouble code definition for code P2101. Causes of error P2101
If I had to guess, something in the Drive by wire throttle body is not playing nice. Unfortunately, I have no knowledge or experience on how these systems work, so I won't be able to help out any further.

Have see a lot of throttle bodies replaced(the dual sensors and the motor that moves the throttle plate), and next thing you know it'* a temporary fix.....first place to look, is the harness connections and the harness wires to the throttle body.....have seen the wires break inside the insulation where the wires attach to the connectors in the harness....this can cause intermittent problems, and unnecessary replacement of a throttle body....rarely find a problem with the PPS, pedal position sensor....


Basically, when you step on gas pedal, this changes the value of the PPS, which is read by the PCM, which then commands the TB(throttle body) motor to move...two tps sensors verify movement of the throttle plate and that it is in the proper position....If there is a problem, a codes is set, and the vehicle is put into limp mode, or reduced power mode...what this is, is the PCM opens the throttle plate a certain amount, and no more....just enough to get home....