Findings while investigating misfires
 

I think I figured out what was causing my random misfires (#1), but want to get your opinions on other findings!
First the car history/background:

1. 04' GT 6-speed with roughly 34K miles
2. Flash up to date except for the 3/14/08 (MSP16)
3. All recalls performed
4. Spark plugs changed last year (roughly 7K miles) with MazSport's NGK plugs)
5. Plug wires replaced same time as spark plugs (AutoExe wires)
6. Still running stock coils
7. AP pulley
8. AEM CAI
9. AP exhaust - stock cat reinstalled last year (from AP midpipe)
10. Optima red-top battery

Now my misfires started just before winter and continued this year, I found water in my intake pipes. I removed the pipes to dry and cleaned the filter since I had it out. Cleaned the MAF sensor with contact cleaner and reinstalled (along with the PCM reset).
It would go a few weeks without a misfire, then it would occur again. Now I know that misfires are common, but when I receive a misfire, the engine would bog (as if the engine was flooded with too much liquid or not enough... either way, it didn't sound pretty). I would do a PCM reset and go about my way.
So I decided to start the usual "checklist" for misfires. I didn't think it was the spark plugs (ok.. I was too lazy to take them out, but with replacing them last year, I thought it was a stretch). I checked the spark plug wire boots to ensure that they didn't come loose, all appeared normal. So now I'm to the coils (which are still stock).
I removed them a saw the white marks on the bottom (3rd pic attached). I also noticed some black crud where the plug wires go (1st and 2nd pic... didn't come out that well). I cleaned them out with a q-tip and contact cleaner. I also ohmed the coils and found that they all read the same. Terminals A/B measured 1.6 - 1.7K while terminals C/B and C/A measured 2.5 - 2.6M.
So I decided to swap the leading and trailing coils (same rotor) to see if it got better or worse. Then I was going to swap the coils to different rotors and see it it misfired the other rotor. Of course I kept the plugs/wires true... only the coils were swapped.
While reinstalling everything I noticed water (once again) in my intake couplers. Now I'm pissed. I felt the filter and there was a small amount collected at the end. So now I'm pretty confident that the intake created the misfire again. I removed the pipes to dry and removed the MAF sensor to clean with contact cleaner. I'll have to wait for the weekend to let the filter dry out in the sun (this filter does not air dry well while indoors).
So I performed a reset and took it for a spin. As I was turning, I accelerated hard and the CEL came on again with the engine bogging (but not that bad). I started to think back and everytime I had a misfire, I was turning and accelerating hard. So I believe the the collected water from the filter just rushed-up into the engine.
WOW... my hands are getting tired.
So now my question... since the coils are showing signs of going bad (white marks) but ohm out just fine, is it worth replacing now? I was planning on purchasing the MazSport Ignition Solution with the government rebate check, but now I'm thinking that a new (different) intake is needed.
Any opinions are welcomed and appreciated.

Well i would get the mazsport ignition solution. I have to on my NA rx8 and you can feel the difference and they last longer than the oem coils

Yeah... I've already started going through my finances to determine if I have enough for the MazSport Ignition Solution and the Racing Beat intake.
I might have to contact Scott and have him include these with my dual resonated midpipe order.

The white marks don't necessarily mean that the coils are failing....

But it doesn't mean that they aren't either ;)

I'd be interested in proof. I've read every post in their thread and no longevity tests have been completed. In fact only one person has 10k miles on them. Don't BS folks.

A lot of the longevity claims will be based on the coils use on other applications...

They will last longer than the OEM coils ....we know they are crap!.....end of story

Correct... thats what I'm wondering. There are white marks, but they ohm out just fine. Are these marks an indication that failure is soon to come, or have we seen coils last many many years with these markings.

jon316G,

if you are worried about your coils, show the bulletin to your dealer and have him to test the coils as in: http://www.finishlineperformance.com...16-07-1793.pdf

how come the misfire situation has been on this long?
what did your dealer say?

The stealership!? :)
I can see it now... they look at my engine and see that I have non-oem plugs, non-oem plug wires, aftermarket pulley, and aftermarket CAI. Yes they have to prove that one of these created the misfires, but they have so much ammo to use against me and is not worth fighting it (unless I knew that the engine itself was dead... then I would take the time (and money) to get it back to stock... better than buying a new engine).
I also didn't take it to the dealer because I like to troubleshoot my own problems. I don't like to depend on others to do the work for me. I better learn this engine now while I still can (my bumper-to-bumper warranty is already up... powertrain is all I have). Not to mention that moisture in my aftermarket intake will not be covered under warranty.
Thanks for the posting the coil inspection document... thats what I used to inspect the coils.