Hi guys,First post here & I have a ? for you,A good mechanic friend of mine has an '99 4.6 F150 that is missing on the number#2 cyl. He has swapped coil packs,changed plugs & wires,swapped out injectors,changed the egr valve & sensor,checked the inj.harness,& at my suggestion even pulled the rocker cover to see if it had a rounded cam lobe but the engine still misses & the check engine light is on but he has had the engine scanned & no codes show up,any ideas? Thanks! Scott

 

A couple of things it might be. first check the injector drive on #2 cyl. with a test light or a noid light while cranking the engine-- you should be getting a steady pulse/flash of the light. If the injector driver seems OK, then check the ignition coil driver the same way with a test lamp. You never mentioned a compression test on that cly., you should test it as well. No injector or Ignition coil drive means a defective PCM or wiring harness/connectors. Hope this will help!