'97 Aerostar misfires on 3 cylinders

[rallyhard]

Hi, I originally posted this in the Aerostar forum, but then I noticed that there is an engine forum, so I figured I'd post it here. A mod can delete the other thread. Here goes...

Hi, I have a '97 Aerostar with the 3.0 V-6 that started running poorly the other day while my dad was driving it.

It started misfiring and losing power on some hills and the check engine light came on, and it got to where it's now misfiring continuously. Right now, it starts right up, it idles pretty rough, and smooths out alot when you accelerate. It's lacking power, too.

We scanned the trouble codes and there are 3 of them. They were the codes for misfiring on 3 cylinders. The P030x codes. I don't remember which specific cylinders they are, but they're all on different coils. They were also not all on one bank of cylinders.

We tried swapping the plug wires from one side of each coil to the other side, and the miss stayed on the same 3 cylinders. We checked and have spark. We have replaced the spark plugs, coil pack (which went bad and was replaced along with 1 plug wire last year), the computer, the camshaft position sensor, tried new plug wires, and checked compression on 2 cylinders. We check one cylinder that it claims is misfiring and one that isn't, and they were comparable, but maybe a bit low. (Around 130psi, I think.) We pulled the fuel filter and blew through it easily, then checked the fuel pressure at the fuel manifold and it was fine.

We have a struggling home business that relies on this van, and we're at the end of our ropes!

Does anyone have any suggestions?