i have 97 4.6 and am having some serious troubleshooting issues. I am experiencing misfiring in 2 cylinders. One cylinder fires a couple times at start up but then dies completely and will not register any spark at all. The other will just misfire randomly. I have replaced all plugs and wires to OEM as well as the coils. I am about to purchase $300 ICM and am wondering if you guys think that is the problem or if you have any ideas.


Thanks a Million

 

The couple of times my 97 F150 4.6 has done this, it has been plug wires. It only does it late in the afternoon on holidays, too.

It has thrown the CEL, and my code reader has told me which cylinder to change. I have yet to change the coil packs.

I would pull the codes one way or another before I changed any more parts. There are other items, sensors, etc, that may be part of this, and you do not stand much of a chance with just luck... imho.

 

the only codes that are tripping is misfire cylinder #'s

 

Before spending more bucks - switch the plug wire (both ends !) on that cylinder with another one - there is usually enough slack to do that. Even if the wire is brand new, I have had a bad one ( and yes it might just have ended up on the same plug as the previous problem - unlikely, but better odds than the lottery).

Happened to me !

 

I will give it a shot

cheers!

 

If everything else checks out ok don't forget the fuel filter.

 

yeah i was having trouble with my 5.4 stalling, and someone here suggested changing it, problem went away. now she's running like new