New EGR Valve

Hi I have 97 Bravada that had a bad egr valve I replace it with new one and when its plugged in it still runs rough and has random miss firer. Run with it unplugged runs better but still a dog with no power .

Your computer might not know it's there.
You might try a re-boot by disconnecting the negative battery cable for 20 minutes, turning the headlight switch on for a second to be sure nothing is holding a charge like a capacitor, then re-connect the battery cable and test ride.

Yes sir I did that . Seem to run ok at low speeds getting on the freeway it cuts out tranny shift down and then it bogs down. Get off gas tranny shift back up but still no power.

Is the Check Engine light on?
It sorta sounds like low fuel pressure too.

Yes check light is on . That was going to be my next guess. I will have it tested

Find out anything?