Okay all you Ford ignition experts (mystery solved)

Here's the post asking for help:
>A couple of weeks back I posted a request for Help with an ignition >One minute it was running fine, the next it was missing and popping
>with the service engine light blinking.
>I replaced one coil and that did nothing. Bought another coil and a >set of plugs. Installed the plugs and viola! it ran like a top again. >General consensus was it was the brand of plugs (Bosch Platinum) that >caused the problem. The Bosch plugs had few miles on them and looked >fine. In spite of the fact the replacing them fixed the problem I >always had this funny feeling about the whole thing.
>Friday it started missing again. I was stumped. The only thing I >could think of was to open the hood at night and check for a light >show. Did that,...nothing. <end>
Here's the source and solution:
Most of the replys were pointing toward the spark plug wires or boots (pin holes or carbon tracked. Three mentions of dialectric grease and one suggestion that maybe a bad brain box.
The wires and boots seemed in good shape and I had never heard of dialectric grease, (wasn't used on the original boots). Turns out that moisture around a couple of the boots *was* the problem. The source of the moisture was a leak around the thermostat housing. If I accelerated fairly hard it would flood the two plugs right behind the thermostat.
Whenever it missed I would wait for it to cool down before checking it out and by that time it was dry enough not to catch attention. Replaced the O-ring and cleaned up the housing but still had to add a bit of silicone to completely reseal the housing. Pretty crappy design IMO. Thanks again to all who replied. One to file away?
Frank
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F.H. wrote:

Frank, I'm glad you found your problem. IIRC your car has a 4.6L with ~60K miles, my ISP has deleted the first few posts on your subject. If the leakage from the thermostat housing was fouling the plug wires, it would probably be a good idea to replace the wires. The rubber caps on the lower ends of the boots "should" have kept the moisture out of the boots and away from the high voltage. This is assuming that the coolant was getting down into the spark plug wells in the intake. If it was pooling around the top of the boot and causing arcing, they need to be replaced for sure. The wires themselves should maintain their integrity even if soaked with water or coolant. If the arcing was down in the wells, I've heard that the rubber seals are available for the lower ends of the plug wire boots. I've never used them, so YMMV. If it were my vehicle, I would just replace the plug wires as preventative maintenence. The wires on 4.6s can start to fail between 60K and 100K miles, in my experience about 80K. The dielectric grease was used on the originals but not in copious amounts. If you pulled a spark plug you would feel an oily film on the porcelin near the top of the plug.
         Just a heads up.             Regards,Tom Adkins
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Tom Adkins wrote:

<snip>
I figured that many would have settings that hold only 1000 or so posts, that's why I posted a bit of the second post.

I've got 130K on this one. I seem to recall some posts that suggested problems with other than Ford wires. Is that so? Also, do you have a wild guess as to what Ford gets for new wires?

Ah hah, thanks for clearing that up. "Heads up" much appreciated.
Frank
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F.H. wrote

My server has pretty good retention, but I flushed my cache and my server only gave me a few followups to your post.

Dielectric grease....

At 130K you're overdue. Your Ford dealer would want a small fortune but Motorcraft wires are available in the aftermarket. My local Autozone sells Motorcraft plug wire sets for your 4.6 for $68.99 per set retail. Stay away from lower cost wires (and Bosch, their plugs cause probems in Fords so I wonder about their wires), they tend to burn internally quicker. For example, I bought a 1986 Taurus w\90K miles in 1994. It had 2 month old yellow ACCEL wires on it (old wires and receipt in trunk). 2 months later it started losing power with a random occasional miss. Turns out the 3.0L ate up the $50 Accel wires in short fashion. The center cores had burned away from the coil towers. A GM tech friend also advised using only AC Delco wires on GM cars for the same reason. It was a lesson learned. That $70 may seem steep but remember, your original Motorcraft wires lasted this long. You will likely never replace them again.
            Regards, Tom Adkins

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wrote:

was no mystery to me you FOCKTARD
lmfao
hurc ast
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