i have a trans am ws6 -00 and the gearbox is a automat, its shift the gear realy fine byt when i do a kickdown the transmission shift the gear realy hard, then i turn to the side and turn off the engine and start again the transmission shift the gear realy fine again, i can drive many miles but its only when i have a kickdown the hard shifting begins, i am really glad for any answer that can help me

Hs: Per from sweden

 

any trouble codes?

 

yes its was kod

P0300
P0412 X2
P0449
P1415 X2

any ides about whats wrong? thanks for the help