Download ISSUE Engine miss, spark knock, buck/jerk, surge and other driveability concerns may be caused by induction crossfire. This occurs because of improperly routed spark plug wires. ACTION If spark plug replacement is performed, the correct firing order and spark plug wire routing is essential to prevent the possibility of induction crossfire between cylinders. Refer to the following procedures for inspection of the spark plug wire routing and firing order. Properly reroute the spark plug wires if required. FIRING ORDER • The firing order for 1987-1993 vehicles is 1-5-4-2-6-3-7-8. If #7 and #8, or #2 and #4 spark plug wires are routed next to each other at the separation bracket, an induction crossfire • The firing order for 1994 vehicles is 1-3-7-2-6-5-4-8. On these vehicles the #1 and #3, or #5 and #6 spark plug wires must be separated to eliminate the possibility of an induction crossfire. • To eliminate the possibility of the coil wire becoming disconnected, route the coil wire under the spark plug wires at the distributor cap. 1987-1993 VEHICLES 1. Inspect the routing of the spark plug wires. Refer to Figures 1 and 2. improperly routed spark plug wires. 2. Make any spark plug wiring corrections as required. 1994 VEHICLES BRONCO OR F-SERIES 1. Inspect the routing of the spark plug wires. Refer to Figures 3 and 4. 2. Make any spark plug wiring corrections as required.