Where is coil pack 3 and 6 located on a 2001ford expedition

You need to check your coil pack.. I am not for sure but the ford exporer has a coil pack for each spark plug located on top of the sparkplug. I have replaced all 8 of mine on my expedition.

Your car either has a 2.0L or the 2.4L 4-cylinder engine. All 4-cylinder engines are super easy to locate the cylinder orientation. Find the front of the engine where the belts are, the closest cylinder at the front of the engine is #1. Followed by #'s 2, 3, and 4 all in order. The firing order is 1-3-4-2, but that is only the order that they fire in, not there location. So #2 is the 2nd coil back from where the belts are.

I hope this info helps!
~subyguru~

No coil packs have nothing to do with transmission. I also believe you might have been charged for a repair that wasn't necessary the transmission. When a mechanic says I need a repair they have to prove it

a very common problem for the 5.4 fords is the coil packs going bad. normally misfires once heated up and under slight load ( in overdrive going up a grade) if the check engine light is on, it can help pinpoint which cylinder is misfiring. if plugs haven't been replaced within last 50-60k miles, plan on replacing plugs, and usually the coil pack that goes bad is one of the rear ones, but impossible to tell without a scan tool. if you don't own one, take it to a shop

1997 Ford Explorer 2WD / 4WD
4.0 liter SOHC V-6 VIN "E"

Firing order 1-4-2-5-3-6
cylinder # passenger side front to back 1-2-3
Cylinder # driver side front to back 4-5-6

Coil pack # passenger to drivers side firewall 1-2-3
coil pack #passenger to drivers side radiator 5-6-4

unfortunately it is not easy to replace. the pump is inside the fuel tank therefore the tank has to be removed to replace the pump.

on the top of the engine under each coil pack
if you are going to attemp this u want to consider buying new coil pack insulator boots
plan on about 4 hrs get your self a spark plug socket with the rubber insert your gonna need it. be very careful removing and installing new spark plugs their is only an 1/8 to 1/4 inch thredded port and it strips out easy if it does u have a another nightmare on you hands if it's running good don't touch a dam thing you will be glad u didn't this job is not easy. alot of things need to be removed to access all the plugs.

no special tools,this is what tools you will need:.7mm socket for the coil packs where underneath them is a deep hole and down there is the plugs---8mm socket for the fuel rail bolts(for the left side sitting in it)which i would use 1/4 inch drive for these--- 5/8 plug socket---6 inch extension---3 inch extension---ratchet---swivel---which i would use 3/8 inch drive for these---and maybe long needle-nose pliers incase the rubber boot from the coil packs come off and sticks to the plug.

I personally would start with the one that runs cylinder #3 and then take it from there.

An O2 sensor will not cause a miss, period. I would think the problem may lie with the #3 coil, or the wiring to it. What are the trouble code(s), give me those and I can be more helpful