Q: code P0102, p0300, p1515 Chevy

If these codes, and the reduced power, occurred immediately after the throttle body service, the throttle position sensor outputs should be confirmed. You may see a yellow wire from the throttle body. That wire has been reported to often develop a break and, in addition, the ground wire in the bundle often has a poor connection to the body. There might be a PCM update for your vehicle as well, relative to this issue, and so the calibration of your present PCM should be compared to the latest available. If a wire break, poor ground, or out of range sensor outputs (as read on a scan tool) do not account for the problem, the recommended service is a Check Engine Light diagnostic. If you request that service, the responding certified mechanic will get this diagnosed and resolved, right at your location. If you have further questions or concerns, do not hesitate to re-contact YourMechanic because we want you to make the most of your repair dollars and help you to get the best possible results.