Coil pack problems

[tman44]

Hey all, I was trying to do a compression test on my 2000 explorer xlt. I unplugged both coil packs, removed spark plugs and blocked open the throttle per the instructions in repair manual. Motor was only turned over four strokes. When I put plugs in and plugged coil packs back in engine ran rough and cat converter glowed red hot. My code scanner said #1 coil was bad, #2 coil was bad and #4 coil was bad. Did I do something wrong following the repair manual? Any information or advice would be appreciated.

 

[Mbrooks420]

Check your order again, it’s not intuitive how it lines up.

 

[J_C]

Welcome to the forum!

If it runs that rough starting it, shut it off immediately so you don't burn up the cats.

Two ("both") coil packs mentioned, assumes it is the 5.0L V8. It would be good to list that on your profile Year, Model & Trim Level, or in your sig.

Does unplugged both coil packs mean you removed the harness connectors on the side of each coil pack, or that you removed the spark plug wires?

If you removed the harness connectors, might have mixed up which goes to which coil pack.

If you removed the spark plug wires, might not have put them back on the right coil pack position, or less likely might not have put the spark plug end of the spark plug wires, on the right cylinders.

Failing any of the above, especially if the spark plug wires are older, disturbing them might have caused breaks in conduction so they need replaced.

I am wondering though, did the code scanner literally state a coil and its # were bad, or just give codes for specific cylinder misfires? ... not that it really matters, since it seems pretty clear it's misfires due to ignition issues.