21bigblock

Hello I just went through putting new plugs and coils on along with new valve cover gaskets. I got it all back together runs good no codes but now the transmission wont shift from 1st to 2nd for an extended time and then when it finally does it shifts extremely hard. Is it possible I may have unhooked something electrical to cause this? Thanks for any and all input.

TrueGS300

Did you have the battery disconnected? You may need to reset the computer by removing both battery cables and holding them together for a moment. Loss of battery power can cause several issues in these cars. TCM may see the loss as a problem and malfunction until reset.

hypervish

Sounds like you may have forgot to re-attach the ground cable behind the intake manifold. I did the same thing and had almost identical symptoms.

rx4rr

Have similar problem: immediately after changing injectors I have rough & delayed shifts, primarily 1 to 3 & 2 to 3 and down shifting. No display warning. Is it solenoid or connection to solenoid?