i have 1993 geo metro and when you put it in drive it will not shift on its own . you can start out in low and shift manually and run great but will not shift on its own
That sounds like a problem with the governor. I would let a trans shop look at it. There is a tap in the side of the case where you can check governor pressure. It should read 1 psi for every 1mph. Example: If you are driving 10mph the governor pressure should read 10psi. 15mph = 15psi. If you are reading 0 psi at the tap at any speed, the governor is bad or stuck.
transman
On this forum, when it comes to all things transmission Transman is “the man”. He’s the resident guru in this field. Follow his advice.