OK, drove my 2003 F150 4.6 today after washing engine yesterday. Now all of a sudden after the wash job my engine is idling very rough when I come to a stop sign or red light. I drove it to the doctor today, 12 miles, idled rough, drove it home and it seem to get better but still a little rough sometimes and OK sometimes. But when I almost got home for the Doc's office the service engine light came on. Took it to AutoZone. It read that #8 cylinder is misfiring. AZ guy said I probably got water down in that coil pack. I asked if it would dry out and he said maybe, maybe not and that I may have to replace that coil pack.

What do you guys think? Will it dry out in a day or two or should I look into replacing the coil pack? Is it hard to do? Where is it located, what does it look like? I also read where it is a good idea to replace the boot along with the coil pack? Again need your opinion. I would like to do this myself if anyone could possibly give me a little guidance on what to do. That would be greatly appreciated. Thank you so much for your help. I am really bummed out as I just bought the truck last week and it runs great and now I have possibly screwed something up. Could kick myself in the you know whatee.

 

Yep, sounds like you got water in the coil. I would replace it along with the spark plugs, and boots (since you are pulling one coil you might as well change the plugs).

 

Thanks 00gstang. Any idea what kind of labor hours we are looking at here. I am a disabled retiree and have no idea if I can afford to fix it. Please let me know. Thank you.

 

Well you can have just the one coil replaced .... for one coil they shouldn't charge you more than 1 hour of labor, plus the part. I would imagine you are looking around $150-200 total.

 

you might get lucky if you did not get too much water in the hole. Same thing happened to me last week. Mine was on #7. I had to have my mechanic reset the computer. Luckly I did not have to replace the coil pack.He told me never to wash the engine again with the hose. There is a posing very similar to your that I made last week. EAsy to find.

 

You can possible fix it don't buy a new coil pack. Remove the coil pack that is giving problem. Place coil pack in the oven on LOW for an hour or so. Temperature should be below 200 F. The moisture will dry out. Inspect the unit very closely after it is removed from oven and look for a crack in the potting material on top or on the sides. I had a crack in the potting material in one of my coil packs. Buy a tube of RTV 100% silicone from the hardware store for $5. Appy a good thick coat of RTV on crack and let dry for an hour or so. I added enough silicone to the top if my coil pack to preven water from pooling on it. Re install coil pack and I bet you will not have the problem.

I work in the electronics industry and am familiar with potting material as well as silicone. If you are able to dry out the moisture that worked its way into the crack and then seal it with silicone you will not have any problems. Good luck!

 

I'm with Vinobambino. Dry the Coil pack out as quickly as you can and check for damage. Driving it with the moisture trapped in it can cause the coil to fail eventually. The sooner it gets dried out the better.

 

Can't tell all of you guys how much I appreciate your time and suggestions. People on this forum are so great it is unbelievable.

I've got a mechanic coming over Thursday to try and dry it out ($30), if that doesn't work then he will replace it for an additional $10, total $40 plus parts.

I am pretty mechanically inclined and can do a lot of things and I would try and do this myself but I have no idea what a coil pack looks like or where it's located so that I could remove it. The Azone guy said it was the one on the drivers side of engine in the very back, and hard to get to. I tried looking for the back plug (nearest firewall) on drivers side and I think I saw the plug but I don't know how in the world you would get to it. Still I don't know what or where the coil pack is located or what it looks like so I guess this is just one I am going to have to hire out and learn from my stupid a_ _ mistake, albeit a costly one for someone on a fixed income. Oh well, what do they say, "Live and Learn", I certainly have done that in this case.

Again my thanks to each and everyone of you for your help and time. Your suggestions and advice have been great. Have a great week everyone.

 

wtf?!?! Do not put the coil pack in the oven!!!

 

Trying to "dry it out" may or may not work....I would just replace it with a new OEM part (Motorcraft part, not Autozone or others)