high RPM's with tranny slip

1996 XJ 4.0L AW4 stock. (DD)

While coming home from work the otherday it felt like the tranny was slipping RPM's went to about 4000 - 6000. so I tapped the accelirator but got no response.. so I pulled over to the side killed the xj let it set and restarted it. drove fine for about 10 -15 min then did it again. also that anoying little orange light came on.. checked the codes all I get is code 43 missfire, don't know what that means. any additive or anything to clean out tranny with befroe it explodes on me.

any idea what it might be. with tranny and missfire??

thanks in advance.

Unplug the TCU and drive it shifting manually. If all is well, mechanics and hydraulics OK, and you have a TCU\wiring\solenoid problem.

This is assuming that the quality and quantity of the fluid in the slush box is up to specs.