1994 Cadillac Concours V8 Front Wheel Drive Automatic 145k miles
my 1194 concours is equipted with a 4T80E transmission, when cool to cold it will shift from 1st to 2nd but not to 3rd or OD, when warm it will stay in 2nd no 1st or 3rd or OD, fluid seems ok, I got no warning it just stopped shifting, I get no message on the dic other than all monitored systems are ok, any ideas?
Is the check engine light working when key is turned on. You should have a fauilt code. My initial thought is that you have a failed or broken shift solenoid. It can still be electrically sound, but hydraulically leaking.