2000 Explorer XLS (V6) misfiring

[tkswan]

2000 explorer XLS (V6) 120k miles. It was misfiring under load. At garage idle he exaust smelled rich. I could clearly feel the misfire when holding my palm about 6" from the exaust. The code reader (at O'Riley auto parts) reported a misfire on cylinder 6. I cleared the codes and took it home, about 3 miles, ...under the assumption that the sensors stay in a not redy state for about 60 miles.

I changed all the plugs and plug wires. During the test drive the check engine light started flashing then it eventually stayed on. The misfire is now replaced with a steady vibration. It idles smooth in park and it vibrates when in gear at a stand still. The palm under the exaust test is 100% better but The fuel still smells rich. I checked the plugs and plug wires and everything seems to be in order. Actualy I replaced everything one plug and one plug wire (or cylinder) at a time to avoid accidental switching of wires.

Help?

[shorod]

It is possible that you have a bad coil causing your misfire. I had to replace a coil on my 2000 Mountaineer V8 recently with only 93k miles on it. I've also had to replace the Mass Air Flow (MAF) sensor, but that was providing an "intermittant MAF" code which made it easy to diagnose. When it was failing, it caused what felt like an extremely abrupt misfire.

Also, what type of spark plug did you use? There have been reports of non-OEM style platinum plugs causing issues.

-Rod

[tkswan]

I went from Motocraft Autolite 103 to Champion 3401. Both platinum. I ususlly go with original equipment but they was out. Is there a test I can do to the coil? A diagram somewhere that will show the configuration of the plug wires to the plugs. I am certian they are right but I want to do some kind of sanity check on those plug wire connections. So far im out $20. The wires was lifetime warranty. Last thing I want to do is start throwing parts at it not knowing if it will fix the problem. Also, whats with the sudden rich fuel mixture odor in the exaust? Are you the same rod that helps me on my 2002 LS?

[shorod]

Yep, I'm a moderator on the Lincoln LS forum as well.

There are some resistance measurements you could do on the coil, but if it passes the measurements, I wouldn't say that means the coil is good. At best, it would just go from "definitely bad" to "suspect."

Maybe the first thing you should do is make sure the plug wires are all properly seated. I don't think the standard Champion platinum plugs should be a problem. If you went with a multiple electrode plug or similar, then I would suspect them.

I should be able to come up with the plug wiring diagram as well as coil resistance specs. If you'd send me a Private Message with the request and an e-mail address that can accept PDF attachments, I'll send the info your way once I get home to my service manual.

-Rod

[tkswan]

sent you my email address. The exaust smells like something is burning.

[tkswan]

...looks like the order is as follows. i have it set up correctly:

--cylinder order--
right side front to back 1-2-3
left side front to back 4-5-6

coil. the connector is on the right side of the coil.
right side (of coil) front to back 1-2-3
left side (of coil) front to back 5-6-4

[shorod]

Yep, that all agrees with the factory service manual. When you say "right" for the cylinder numbering, you are referencing sitting in the driver's seat, correct? If you are standing in front of the Explorer with the hood open looking at the engine, the left side of the engine is bank one. Cylinder #1 is nearest the belt.

I've sent you a couple of attachments detailing the misfire troubleshooting process.

-Rod

[tkswan]

Thanks for the information. We are on the same page as far as wiring and cylinder placement is concerned. I don't have the necessary meters to perform the required tests in the procedure but I put my old timing light on each plug wire and there is no strobe on numbers 3 and 4. So i guess I have my culpret. I am going to get a coil pak. That also explains the raw fuel smell.

[shorod]

Please post back when installed and let us know the results! Good job improvising on the test!

-Rod

[tkswan]

The coil was the problem. The "exploder" now runs like new again. I guess a good coil test is a basic timing light. Even though there was no spark to ignite the fuel, the strong exaust smell was because the block was hot enough to smoke it (the fuel) through the exaust, you see no smoke but you will smell it. Trust your sense of smell.