P0354 misfire on cylinder 4 Ford F150
P0354, misfire on cylinder 4, Ford F-150, check engine light on
Ford has issued a technical service bulletin (TSB) 04-21-10 to address problems with a P0354 misfire on cylinder 4 Ford F150. The problem has been linked to 2004 F-150 models and has been traced to the A/C line coming in contact with the wiring to #4 ignition coil.
If the harness is coming into contact with the A/C lines, here’s the fix. Disconnect the battery and then reroute the main harness. Remove the two harness connectors on the right hand side of the engine. Then inspect the wires for ignition coil #4 for damage. Fix any frayed or chafed wires. Then move the entire harness away from the A/C line.
© 2012 Rick Muscoplat