2004 Cavalier. Daughter's car.
Torque converter won't lock up on it's own. When Tech2 is hooked up while on test drive, they can make trany do everything it is supposed to, including locking in the converter.
Is it possible that the radio plays a part in computer communications?
This car was previously screwed with someone installing a cheap quality stereo.
Coincidentally, the stereo hasn't worked right from about the same time as converter issues.
Could there be a connection????
Would getting an OEM radio possibly help???

Thank you for any advice.