I got a code from the OBD that said cylinder 3 is misfiring. The shop I took it to said it's probably the coil pack. I was wondering if it was hard to change out the coil packs on this van (I have the 3.9L), especially the ones on the back.

 

You only have one coil pack. It sets on the back side of the engine. A misfire is as simple as a bad plug or could be a plug wire or yes, the coil pack. How many miles are on your engine? I run Iridium plugs as they require less energy from the ignition system, thus less load on the coil pack. If not done recently, I would replace the plugs with new ones. I always change platinum plugs evey 50,000 miles and replace wires every 4 years regardless of mileage. I run OEM wires as for me, they are about the same cost as aftermarket wires. Easiest way to access the rear plugs and or the coil pack it to remove the wiper arms and the few screws for the cowling, then just pull the cowling out of the way. Opens the whole rear area of the engine compartment up for easy access. Ensure that you use dielectrical grease on all plug ends/wire ends to eliminate spark leakage.

 

Wow, thanks for the tip. I haven't changed anything since I got the van 2 years ago, and it probably didn't have anything done to it before I bought it. The shop I took it to was going to charge me $760 to change out the plugs, wires and the coil pack.

 

No problem. I also use a little dab of Permatex Copper Anti-Seize on the spark plug threads. This helps keep the plugs from siezing to the heads.