Ok here goes it, I have a 1994 XJ five speed original motor developed horrible knock, so i swapped it out for a 1998 or 2001 4.0. It was setup for fuel injection, I removed all of the adapter and the fuel injection from that motor. I assembled all of my 94's Throttle body system also all of its electrical and vacuum sensors. The transmission is brand new with only about 800 to 1200 miles on it, it is not rebuilt new, not reconditioned, it was straight out of the craight brand new. All of that out of the way, It's been almost 2-2.5 years since that i have been chasing everything that i can think think of when i have time. I have replaced the timing sensor that mounts on the front top of the transmission and just behind the Flywheel. Now heres the problem it will not idle correctly, will not rev out above 3500 rpms, will not go above 35mph. Fuel pump is not bad the pressure is correct. PLEASE HELP ME I WANT MY CHEROKEE BACK, IF I CANT GET IT RUNNING I WILL BE FORCED TO SELL IT BY THE END OF THE YEAR. MUCH THANKS TO ALL.