2007 FX2
5.4 3V mfg 03/07
201,175 miles

I was pulling off from a stop sign and I thought the transmission went out. Shuttered and no power, had to feather the throttle to get it to go. Limped back to work and let it set for several hours. Cranked it up and it was misfiring. Opened up torque app and got these fault codes

P0420 - Powertrain catalyst System Efficiency below threshold (bank 1) [Current Fault]
P0355 - Powertrain Ignition Coil "E" Primary / Secondary Circuit [Pending Fault]
P0354 - Powertrain Ignition Coil "D" Primary / Secondary Circuit
P0356 - Powertrain Ignition Coil "F" Primary / Secondary Circuit
P0358 - Powertrain Ignition Coil "H" Primary / Secondary Circuit

I limped it home by feathering the throttle and coasting where I could. Got up the next day and replaced all the coils, it had been about 18 months since I replaced them. Auto Zone Duralast lifetime warranty. Now I am getting codes for misfires on #5 & #6. Idles bad, feels like one whole side is misfiring.

I am puzzled because it all happened so suddenly. Yea I know its got a lot of miles but didn't expect it.
Any ideas where to go next?

Thanks for looking
Jason

 

use decent parts for one...duralast=neverlast

 

forgot to mention, A/C went out at the same time

 

Did you replace all the boots /springs ,carefully clean out wells . Clean snout area of plug with carb cleaner , that carbon breaks plugs . Use just a small amount of dielectric on each end of boot . Do a hospital clean plug job .
Its possible your cats are starting to plug ,if it can't exhale its not going to run good . What does your O2's look like on torque pro . Torque pro can tell you under test results raw computer counts for each cyl building to set a code , zero is achievable.
What plugs are you using ,there are some counterfeit ones out there.

 

Its also possible you jumped time but you don't have the codes for that .I lost a roller on no 8 intake and it sounded bad an ran bad .

 

I used motorcraft plugs when I replaced them. Got them from a local auto parts store so I don't think they were counterfeit, at least I hope not.
I pulled the plugs on #5 & #6 and they looked fine.
I did not really clean out any other well but I did put some Dielectric in the end of each boot.
The wells didn't have anything other than a little sandy type dirt around them, no oil.

 

here is a picture of one of the plugs I pulled out to check. Does it look ok?

 

that looks like absolute garbage....that plug is shot

 

how many years and miles on that plug ?

 

A few lame comments about your codes that might help narrow things down.

1st and most important: P035x is a special animal - technically NOT a misfire. But rather a report that the cylinder couldn't draw a spark when it tried. ( ie: a poor electrical connection where the PCM does not detect 'current' drawn in the primary circuit. OR doesn't see the expected reverse voltage spike in the primary that occurs when plug sparks - right after spark is commanded.) The later might happen with the crappy plug in the photo

This is VERY different from a P030x code, which occurs when the Primary / secondary electrical test are satisfactory and the PCM "DID NOT" detect the epected slight acceleration in crankshaft rotational speed immeiately after commanding spark to that cylinder. ie: too lean or too rich fuel mixture, low compression from valve timing, IMRC, injector or fuel delivery problems.

In your case, the PCM was unable to draw a 'spark' on any one of the offending cylinders. (except in your second statement "I had _misfires_ on #5 & #6" - where the TYPE is undefined).

I agree with @djfllmn , that plug looks like $h|t. I would Get rid of it - and torque the replacement properly. Do a hospital clean plug job as @redfishtd suggested and stop the antifreeze or oil from getting in the well.

Your P0420 code is a normal result of misfires dumping too much unburned fuel into exhaust. Your A/C clutch relay is disabled by the PCM when misfires are occurring. So ignore those issues until misfires are cleared up.