Another 2001 Winny with a bad coil

I have a 2001 Windstar that while driving one day starting running bad all of a sudden and triggered the blinking CEL - missfire on Cylinder 3.

Prior to that, I had some intermittent lean codes that once upon a time had been corrected by replacing the mass flow meter but had more recently returned.

Well, I put a spark/ignition tester (it looks like a transparent spark plug) between the #3 spark plug and wire. At idle, the spark tester looked to be blinking just fine. I went ahead and replaced the plugs and wires anyway and then took it for a drive. Miraculously, at low speeds at low throttle (1st and 2nd gear) the van drove really well. Once I got onto the highway, moderate to heavy load (going uphill) it was definately bucking. The blinking CEL was back, and the missfire again was detected in cylinder #3.

I added fuel injector cleaner, both gumout and Berrymans B-12, and it seemed to run much better. Bucking would still occur but no CEL and generally only in 4th gear going uphill. I thought that it might be a dirty fuel injector. I also performed the quick EGR test, disconnecting the EGR valve vacuum line and the bucking persisted - indicating that the EGR was not at fault. I also checked the vacuum lines that Windywoes had a problem with, but I did not see a problem there.

So, I went ahead and replaced the coil, thinking that this really was a spark problem. Voila! No more problems uphill. It was a bad coil after all.

I did see, after looking several times in bright sunlight, what appeared to be a small crack in the old ignition coil. In my dark garage, I would have never noticed it.

BTW, my van has 117k miles on it.

The reason for my post - to say thanks for everyone's experience in this forum.

I guess the post that I found to be the most helpful was the thought that putting a new coil in at 100k+ on a 2001 Windstar isn't really throwing money away, even if the one in your vehicle is still good. It won't be long before it isn't.

I'll concur with you on this one. I've got a 2002 Windstar with 108,000 miles, and the wife called me yesterday at work and told me that the van was chugging and the check engine light was blinking. When I got home, I checked the codes, and it was throwing a P303, same cylinder 3 misfire.

Looking around on this forum, a guy suggested a quick check; swap wires between cylinder 2 and 3 at both the coil and the plug, clear the codes and run the van. Then see if the code changes from P303 to P302. This would indicate a bad wire. Otherwise, you're left with a plug or coil.

Well, before the store closed, I went and purchased the coil, plugs and wires. The plugs aren't old, so I didn't expect them to be a problem, but I wanted to be prepared. The quick check still left me with code P303, so I decided to pull the coil. The new coil worked perfectly, and when I reviewed the bottom of the old coil, there were small cracks right underneath the plugs for cylinders 1, 2 and 3, with the largest at 3. This just happens to be the closest to the exhaust manifold, so perhaps the heat helps age the urethane bottom of the coil, or something else. Who knows, but for sure, that was the problem.

Now the van runs like a champ again. Like old89lsc mentioned before, seems like a coil change at 100,000 should be listed as routine maintenance.