I have a 1992 trooper Moderate lift and some larger tires, I've only owned it for a little while and it feels pretty buff but when i was doing a simple hill climb in 4x4 it lugged out on me I know the air filter is clean but as far as gas line goes I didn't check any of those filters... any idea where to start? also I think my 4x4 low is out any ideas?

 

how are the spark plugs, have they been changed? Also, how about the EGR Valve, have you cleaned it as well and the EGR bypass tube.

 

my trooper lugged and had random high idle and it was vacume leaks.. could be fuel filter something got in it... and with the 4wd mine stopped working out of no where it was cause of the cv joint c clip popped of so 4wd wouldnt engage and cv would move in and out...

 

I had the same problem with my 2002 trooper and the dealer said it was due to a malfunctiong speed sensor, I replaced that and it still happens. The error code for the speed sensor would show up every few days and then the car would shutoff. Now it maybe the transmisson speed sensor