I have had a wet weather issue twice, once last fall and once this spring. Both times were very wet and damp conditions causing a sputtering and chugging and dying at lights, both times no codes and after drying out in brother's shop it went away. Now this weekend up at the cabin it reappeared, again very wet conditions. Replaced the MAF...no change. Sputtered and chugged my way home with it killing at most stop signs/lights. Finally got home and couldn't even back the TT up the driveway, it would kill. Finally threw numerous codes (misfire in cylinders 1 and 9, and misfire in first 1000 revolutions). I'm thinking COPs as the plugs are not that old and the little research I have had time to do suggests this also. Any thoughts? If it is COPs, I have heard there are some to avoid and some that are recommended? Any info I can get will be appreciated, wife want's to trade it off!!!

 

Really...no one has any ideas?! Maybe the wife is right?

 

I had issues similar to this on my 99 F-150. It was COPs.....you can generally find which one via a scanner when it happens. I don't remember which COP I went with, but it has been over 5 years.......

 

I have had wet weather misfiring with no codes on our 5.4l 2003 Expedition. It was not a problem with the COPs, but with water getting down in the spark plug holes. Water was getting onto 6 and 7 and eventually the spring connecting the coil to the plug got rusty and started throwing codes. Found the leak by taking a garden hose and flooding the windshield. Took awhile to figure out and one of the cats got clogged. Fixed the leak, changed the COPs (120k so it was time) and has been running great.
If it's just one misfiring it's not too bad, but when 2 are misfiring ours ran just like your description.
It started misfiring again at 150k when is was raining (which isn't very often out here) and this time it threw a code. Removed the COP and fortunately I left the connector on until I had pulled it out slightly. The COP had broken at the base of the connector. It was held together by the 2 pins inside. It looked fine, you can't see the crack. Pull on it and it will come apart an 1/8". Any moisture would cause it to misfire. Replaced the COP and runs great.
One of the first things I did with our new to us 2002 V10 Excursion is flood the windshield looking for leaks. I ran a bead of silicone along the plastic molding just to be sure.

 

A quick type of troubleshoot is swiching the coils to different cyclinders and seeing if the code follows then you will know that its the coil for sure and just replace it, iv saved some people some cash buy using used coils seeing how they are a bit expensive, so if you know of anyone parting out a V10 you can always go with that as well. Good luck.

 

Changed the #1 and #9 COP and boots and she's back to running like a top! Thanks for the replies. Thinking about doing the other 8 as preventative maintenance, but at $87 apiece, I'm thinking I'll wait.

 

I've had lots of people tell me you are supposed to change them all at once.

I think replacing them as they go bad is the most cost effective measure. Might throw a couple of new ones in your spare tire cover if it happens again while you are on the road.

 

Not a bad idea, especially since I had to limp her home from the cabin yesterday

 

What did the springs inside the boots look like?
Did the boots have any weird looking spots on them?
If the springs were rusty or the boots were thin the coils may not have been bad.

 

Excursion Tech Folder sticky thread.

General Engine & Engine Compartment Threads > Water Intrusion at the Cowl: Bridging the Gap

I've always changed them one at a time as they go bad.

Stewart