PATS components - Trying to troubleshoot a wicked misfire | Ford Explorer Forums - Serious Explorations

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PATS components - Trying to troubleshoot a wicked misfire


Well-Known Member
April 11, 2007
Reaction score
City, State
Chesterfield, MI
Year, Model & Trim Level
98 mountaineer v8
So heres the story. I have a pretty modified mountaineer, tmh's, e303, performer upper and lower intake, full exhaust, cai, sct livewire from henson perf, modified mustang cast heads. Well after having a bad misfire for pretty much the whole summer, off and on i've got it down to the spark plug wire/coil connection. So I needed a set of spark plug wires, ford coil pack end on the the coil end, tight 90 on the spark plug side (because of the different heads and wire proximity to the headers) so I rigged in some msd wires, bending the female/socket coil ends to fit inside the coil packs. Obviously a bad connection, but it was what i had to deal with.

So I've fixed that problem with way too much engineering. Gently tapping the inner coil contact with a 5/16 tap and Putting a brass threaded "slug" with the inside of slug threaded with a m4 x .7 tap. Then putting a piece of threaded rod with a jam nut on it, then threading on the tip of a spark plug (the same thread size.) All in all, resistances checked out after doing, every contact was coated in die electric grease. Everything checked and re-checked.

So i also had had to change the header gaskets so i inspected the wires and they were flawless. I'm also running e3's, replaced when i did the wires about 3k miles ago. So i go to start it up. Remarkable quieter but still missing.

I put a timing light on the wires and it shows an erratic light pattern, intermittently, across all the wires. So the crank position sensor is ok, clean, checked out, cps is new as of about 6 months ago.

NOW, FINIALLY. So the last thing to check is the PCM. So i picked one up at the junk yard. I got the PCM, the anti theft module, the pick up ring (inside the steering column) GEM module and a key, all from the same year vehicle, (98 explorer, mines a mountaineer). I did not however get the RABS module. I didn't find out about that until recently.

So I swapped everything out, battery disconnected, sct returned to stock mode, proper procedure. Because i could not get the ignition cylinder out of the explorer, i took a piece of wire and wired the key to the pick up ring so i could use my key that is keyed to the ignition cylinder. Everything connected and nothing, it will turn over, but not start. I have a blank, uncut key i was going to have just cut tomorrow to see if my key, programmed to my old computer was interfering with the new key wired to the pick up ring.

I'm just out of options to troubleshoot this misfire. Its backfiring and popping and i'm getting a bank one lean code. Any and all advice would save my sanity. I've got way too much time and way, way too much money in this thing and its getting 9 mpg and running like i'm towing a huge anchor behind it.

Thanks again.

well the no start seems like it has something to do with the PATS system. as for the misfire well.. there usually not difficult to find lol, are u saying the coil packs are new? did u try and pull the injector plugs to see if its a faulty injector? or something of that sort