There should be no need to reprogram an ECM if unplugged, we unplug them for testing circuits in many cases. It sounds like the shops in your area don't know what to look for. Are they not doing a full system scan to see if there are any codes stored?
And is the Check engine light on when its running in Park?
When you say a missing sound, do you mean a hissing type of sound? Does the engine have a rough idle to in Park? Can you keep it running if you were to keep your foot on the gas pedal a little as well as the brake pedal when trying to put it into Drive?
I'm asking because if the engine is not getting enough air to keep it running when put into drive it could possibly stall, so giving it some gas will open up the throttle plates a little and allow more air into the engine. Putting it into Drive does put a load on the engine.
Can you take a video with your phone of it running in Park, and then one with you putting it into Drive, so we can get a better idea of what you are experiencing.
The mechanic should be able to see something out of place with a scan tool, and be able to scan for codes, I'm not sure why they are not giving you more information.
Monday, May 19th, 2025 AT 2:47 PM