An OBD 1 scanner with the Chrylser plug adapter.
The spark plugs on a 1993 5.2 L should be gapped to .035 inch.
OBD 2 doesn't send information any where it has to be read by a person with a scanner when the scanner is plugged in to the dlc plug with the in the on position
The spark plug gap for the 1994 Jeep Grand Cherokee 5.2L (318CID V8 is .035".
It can be done, but it won't be a simple "plug and play" swap.
.034
On a 1993 Jeep Cherokee, the scanner hookup, also known as the OBD-I connector, is located under the dashboard on the driver's side. You may need to remove a cover or reach up to access it, as it's typically positioned near the steering column or the fuse panel. The connector is a rectangular plug with several pins, used for diagnostics and reading trouble codes.
1998 Jeep Cherokee 2WD 4.0L MFI 6cylThe Spark Plug Gap.035 (In thousandths of an inch)
.035".
.035
The fill plug is on the center of the rear of the transfer case.
check the spark plug wires and the distributor cap wires