Sounds like they messed with the timing... Bring the timing back a bit and see what happens.

If the timing was set with the jumper installed, yet the TPS was not properly adjusted, it would be waaaay slow. If they forgot the jumper in place when checking the advance timing (why they would do that, I don't know), it would be 7* too far advanced, and you would get a lot of knocking and bucking out of the truck (as well as being real hard to start).

"A young man who does not have what it takes to perform military service is not likely to have what it takes to make a living." - John F. Kennedy

Proud owner of an 88 Montero (with a blown engine).