The ignition on the old Jeeps is not very good or very reliable.I have an 89 YJ with a 4.2L and the best thing I ever did was to put a HEI ignition on it. I have gained better MPG and more power, plus the acceleration is much better. This ignition does away with the old Distributor and the Duraspark box. The cost is about $190 from CRT Performance.