I'm thinking that I replaced a bad coil with a new, but bad coil.
I managed to find this while searching around -
Truth be told, with the frequency of Ford COP coil failure, Mode-6 misfire history combined with fuel trim analysis is just about good enough for me to condemn a coil anymore. Heck Pete, what's your first thought on a Triton misfire?
But on the current ramping, it is way too quick and simple to pull the coil power fuse (Central Junction Fuse #30 inside George's truck), plug in a jumper and clamp around it there to view all eight patterns simultaneously. It very quickly reveals primary winding faults in the amount of current developed during single strike phase around 2000 RPM, and reveals secondary resistance in the opposing amplitude of the multi-strike events at idle This method is particularly useful in identifying failing ignition coils when a misfire is not currently present, and you don't even need to open the hood. Try it sometime Pete.
most of that is over my head, but the important part here is
single strike phase around 2000 RPM, and reveals secondary resistance in the opposing amplitude of the multi-strike events at idle
That seems to match up my symptoms pretty well.
Not getting the multi-strike in the lower rpms like I should be, but once it kicks over to single strike mode, (and the different fuel and timing map) at the 2k mark, it runs fine.
This is what most people are referring to as a "low grade misfire" on various forums, just no one ever really got to the whole multi strike at idle thing.
can anyone translate what these guys are talking about?
(original thread here -
Ford F150 4.6L V8 troubleshooting)
and/or
can anyone help test each of these coils to figure out which ones are actually bad?
I don't know that I could afford to buy another set of 8, just to shot gun parts and money at this thing.
It would be really nice to be able to replace the one or two that are actually bad.
It is amazing to me that this kind of information isn't more readily available. I've been blown away at the straight up false information that is out there about these trucks. I know it exists with all cars, but you'd think with the millions of F150's out there, that things like diagnosing a misfire would be more knowledge and information based, instead of the "black magic" that is seems to be.
/rant