autolite double platinum misfiring

[FIND]

I <3 NGKs and Denso as well, just figured I would go with autolite iridiums this time

[Tony H]

Many Plat plugs should not be gapped. Not to say to put in a .045 gap plug in where .054 is required. Just that I think you may have put in what some cross reference chart says will fit but in reality it wasn't designed for the 'X'.

Put in plain old Autolites .. what number (765?) or something. Change them out every 30K miles. Forget the Plats. many cars do not behave well with them.

Your miss may be old Wires or you were due for plugs anyway.

EDIT: sorry I didn't read all te hposts. didn't see that you fixed it. Wires

[Roadrunner777]

After sitting on the spark-plug fence for a while, I concur with Tony here. I think it makes sense to use the plug the system was originally designed for.

Designed for? We are just pumping a bunch of voltage and making it spark to ground. I found some schematics for coil packs and this isn't your old point and condenser system anymore. I won't say they are precisely 'tuned', but the circuits were designed and proven with plain sparkplugs.

(All of this is nearly gut feel and should be taken as such)

As a DD owner, I hate to make that conclusion because it means somewhere along the way I will need to change plugs in MN winter, and it is just so special when your tools are freezing cold.

The design of the coil pack really surprised me. We all know that the coil fires in pairs. I expected the pair to be simply connected internally. It isn't that way.

The coil pack floats between the two plugs and sends a + spike out one side and a - spike out the other side. I can't tell if the + and - alternate or if it is always that polarity.

But, it does mean that, if one chooses to use platinum plugs, they need to use double platinum or they will not get even wear.

That's the way it looks on paper. It may not matter at all, and someone who uses single platinum plugs will counter me with 15 years of explorer experience. I prefer experience. Can anyone state that they use single platinum plugs and they wear equally? I'd really like to know one way or the other.

[techieman33]

I've had no uneven wear issues with motorcraft platinum plugs, it's the plug that ford spec'd for it and people have run them for 100k miles with no problems. Should they be run that long, well obviously no. The plugs had to of been way out of spec and the motor was probably down on power but the motors were still running fine. I think a lot of that is due to the power of the coil packs, there is so much voltage in them they jump the much wider gaps without major issues.

[Roadrunner777]

Thanks for the reply, I have been trying to get my hands around the idea of metal erosion and polarity. I remember points, and you would get metal transfer from one contact to the other.