I have a 2003 Lincoln Navigator that is having mis-firing issues. I had the codes pulled and here is what came up:
P0320 Ignition/Dist Enginge Speed Input Circuit Malfunction
P0354 Ignition Coil D Primary/Secondary Circuit Malfunction
P0355 Ignition Coil E Primary/Secondary Circuit Malfunction
P0356 Ignition Coil F Primary/Secondary Circuit Malfunction
P0358 Ignition Coil H Primary/Secondary Circuit Malfunction
P0351 Ignition Coil A Primary/Secondary Circuit Malfunction
P0352 Ignition Coil B Primary/Secondary Circuit Malfunction
P0353 Ignition Coil C Primary/Secondary Circuit Malfunction
P0357 Ignition Coil G Primary/Secondary Circuit Malfunction

Please let me know what you think.

 

Wow, that seems to point at every cylinder in the truck! How many miles on the vehicle? How long has the problem been going on? If for a while has it gotten worse?

Check out this thread: https://www.ford-trucks.com/forums/9...uble-code.html

The TSB mentioned there covers 03 Navi's too. You'll see I found the chafing mentioned in the TSB . I've patched things up and so far no unexpected stalling (day 2). Waiting for the replacement harness that's on order.

May explain some of the symptoms you're seeing.

 

Check your spark plugs for condition and gap as well as carefully inspecting the coils and boots for either hairline cracks or arcing.

 

The coils work by having +12v supplied to one side and the second side receives a ground pulse from the PCM to trigger the spark.

I suspect you're having an intermittent +12v loss from the ignition. Possibly the ASD relay is faulty.

 

All three responses are great and I will check out each suggestion. The Navi is a 2003 with 100K+ miles - great truck no problems before.