ok i was asleep when i hooked up my bat charger backward to my fuse box to open the trunk, but only for 10 or 15 seconds.
then started the car and all was fine for 30min. then the car went into limp mode. sooo i unhooked the batt and restarted all was fine once more restarted the car and it ran fine. a week goes buy (the car was not moved) next start after 5min the car goes back to limp mode.... the batt is now unhooked to reset the computer any ideas ?????

 

Most battery chargers just don't do anything if you hook them up backwards. (mine doesn't) Any lasting electrical effects should be easily tested - look at the voltage with the key on and then again after engine start. It should not be lower than 12 and it should go up with the engine over 2000 RPM. I can't imagine any effects of hooking up the charger up backwards that would not be corrected by simply removing the charger. Now, if you tried to start the car with the charger hooked up, that's a different story.