2003 impala LS 3.8 hards shifts

can anyone help me my impala when i give it gas is a little sluggish then it kicks in then switches into gears hard.i believe my car is also and ex-police car if this helps you help me.ive changed plugs wires fuel filter trans flush and trans filter oil change maf sensor

possible bad cat or pressure control solenoid. do you have the "check engine" light on?

my check engine light is on.how can i check my cat or pcs?

did you have the transmission trouble before you flushed it? Flushing it could have caused some debris to lodge in a valve actuated by a solenoid ie:"pressure control solenoid".

i dropped the tranny pan let the fluid leak out changed filter and put pan back on filled up and still the hard shifts.is the pcs in the tranny or on the outside that i could change without opening the tranny?

PCS is not a DIY job. I would get your car scanned for codes sense the SES is on. usally P1811 <<the harsh shift code will not turn on the SES. Go to your auto parts store they usally scan for free. (Autozone, Parts America)

can anyone help me my impala when i give it gas is a little sluggish then it kicks in then switches into gears hard.i believe my car is also and ex-police car if this helps you help me.ive changed plugs wires fuel filter trans flush and trans filter oil change maf sensor unhook your neg bat terminal for 30 seconds ,hook it back up, then start your car up,let her idle for 60 secs, shut her off again for 30 seconds then start her up and drive her around the block to see if she is any better, this should reprogram your shift patterns for you tranny, thats what the g.m teck at the assemble plant who is the tranny tect did with my car, works fine now, better then it did when brand new, now mine has 30 000km's and since reseting the computer manually the car shifts as smooth as butter.