97 bravada transmission problems

[helpme24]

I have a 97 bravada that recently has had the transmission rebuilt. Now though my car runs until its been drivin for awhile and then the transmission has problems shifting. and even when i press farther down on the gas pedal i actually go down in speed and it backfires. anybody have any ideas what this means? i could definently use the help

[Chris Stewart]

Is the Check Engine light on?
If so, you can get a free scan at most chain type auto parts stores then we can talk about the trouble code here.
Sounds like your motor is running lean due to low fuel pressure. The fuel pressure spec is 60-65psi when you turn the keyswitch on and should hold that pressure a coupla minutes after you hear the fuel pump stop.

This is where it's checked with a fuel injection pressure test kit available at most chain type auto parts stores.