[fgthwar]

Changed the thermostat a week ago after putting it off until it threw an 'insufficient coolant temp' code, and decided to change the plugs since i figured it'd been running too cold for a while.

found two plugs that looked like they were rusty, or even muddy on the outside. the two coils on top of the rusty/muddy plugs had the same gunk on the boots. it doesn't appear to be on the threaded portion of the plug, nor did it appear that the ugly plugs had any different tips than the cleaner ones. i just brakleened the coils clean.

the picture is of one nasty plug, one shiny one.

what gives?

 

[metrocube]

It could be from moisture.

Clean the coil packs and spark plug boots.
Apply dielectric grease around the coil packs and inside the boot.
Reinsert the coil packs into the engine.

for other possible coil pack and plug related problems, see http://www.lotustalk.com/forums/f25/coil-pack-arcing-77822/

 

[Bryker7]

Mine were like that and actually caused slight miss fire, the grease worked but water still got down the tubes, so I sealed the top of the coil packs and its been good now. This was only a problem on the 2 passenger side plugs

 

[Gunpilot]

They all do that. Water runs down inside. Get liberal with the dielectric grease and you can silicone the top of the coil pack. It's not mud, it's rust.

 

[fgthwar]

thanks. i'll give them all a good scrubbin and dieletric greasin. Probably best done with a new set of coils, since it has an ever-so-slight rough idle. I'll update after.