I just bought my wife an 88 XJ it is a 4.0 and AW4 combo, it has a problem staying in OD, if you give it enough throttle it will stay in, but if you let off slightly it either shifts to 3rd or the converter unlocks cant really tell which, i was thinking it might be the TPS and/or the NSS what do you guys think, oh and the fluid is full and looks good, thanks