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Discussion Starter #1
i'm using denso's in 1.8t. the last time i changed the densos, it felt like it was misfiring, but no CEL came on... it eventually died completely. i changed the plugs and all was great (for another 15,000 miles).

so it starts "misfiring" again, and again, no CEL. i go get some more densos, but hadn't found time to put them in...

this morning, the car started and immediately died. so i put the plugs in... it took a little love, but it is once again running, and running well (no misfires, no rough idle, no nothing)...

the question is what i found on the plugs, in the coilpack boot, and on the ENGINE SIDE of the plugs...

it looks like some kind of reddish granules, and where there appeared to be a fair amount of this, it turned into what i would call a coke. i have no idea what it is, and/or what this is indicating...

i have taken several pictures of this, the large, high resolution pictures are in this directory--> HERE...

this is a small version of the pics...

single denso



denso comparison



looking into the coilpack



looking down on the plug




ANY HELP from the gurus would be most appreciated...


thanks...

---todd
 

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From what it looks like in your pictures, maybe a dried out grease from the coil pack connector or cosmoline off of the plugs? Is it on all the plugs? Very strange. I had a misfire situation at one time. I found water below my coil packs. Dried them out, placed a litle vaseline on the coil pack o-rings and it was all good from there.

P.S. What camera are you using. Amazing pics...
 

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You might have a faulty coil pack or is about to go dead. The Coilpack for that plug must have exploded. Try to clean it up before you install a new coil set.

Does all 4 look like that or just one?...
 

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I just posted a question this evening also about some debris I found when I changed out my plugs this afternoon. The stuff I found appears to be the same as what's pictured on the threads of the upper plug in your "denso comparison" photo. All of it was gray to black in color. Since the coil pack has a rubber ring around it that fits it in place, I doubt that that junk could have fallen in around the plug. It must be something from the coil pack itself degrading.
 

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Wow... replacements every 15k? It would seem that any cost difference between the Denso's and Bosche platnum's would be augmented by the shorter replacement intervals (almost 1/3 the time). I have never seen that before, it looks almost like a rusted contact on a battery...
 

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Discussion Starter #6
i don't mind changing plugs... it's easy to do and it gets me in there to have an occasional look-see... i don't know how much the boshe platnum's are, but the denso's are about 1.69/ea.

this condition is on ALL coilpack boots and on ALL plugs...

and everything is running fine now... :crazy:

it looks like the coilpack boot snaps off the coilpack itself, and may be a part that i can purchase separately... i did use a can of compressed air on everything to blow away the loose granules and coke, and it did a "decent" job; i doubt they'll ever be the same, though...

btw, badWGN, the camera is a Minolta DiMage 7i. it's freaking sweet, had it about 7 months now, i'm around 5,000 pics so far... :lol: :D
 

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i've seen that before on a 2001 1.8T GTI, when i was doing my work term at the local VW dealer, anyways that redish shit is the dielectric grease that comes on the coil packs and spark plugs from the factory, if you have a less than great connection between the plug and coil pack hte spark will burn up the grease and cause it to look like that. :suspicio:
 

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improperly gapped spark plugs will put stress on the coil packs. Try to use single probe plugs and gap to 0.032" as recommended. If you're already going through set of plugs every 10/15K miles, then I would also recommend using the copper based plugs like NGK BKR6E or Autolite 3923 instead of platinum or iridium plugs.
 

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Discussion Starter #9
that redish shit is the dielectric grease that comes on the coil packs and spark plugs from the factory, if you have a less than great connection between the plug and coil pack hte spark will burn up the grease and cause it to look like that
does it granulate too? i.e. is that the only thing that is on them?? and more importantly, does it completely burn off over time or how is it cleaned?
 

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What's your year/engine code? If you've got the old style coils that went on the AEB 1.8T with the separate neoprene output stages, yeah, you can buy those separately, but when I asked for a quote I was told $25 each. $25 each for a piece of neoprene with a little looped wire in there...
 

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ive never seen di eletric greese turn red like that

i guess if it was came loose and was arching threw it or soemthing but it almost looks like sand to me
 

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Discussion Starter #15
What's your year/engine code?
it is an AEB... do you have a part number for those by chance? if not, i'll probably call the dealer.

i would also change coil packs and spark plugs, anything in the system that would be bad.
i'm hesitant to do that if only because the car is running fine right now. i can see switching the "neoprene output stages" as rechtsfahren is calling them, because they look horrible, but not the coilpacks too...

Looks like the engine was snacking on Baco-Bits on a salad with crutons and ranch dressing.
that actually made me laugh out loud!!

...

i have used dielectric grease in the boot before as well as some anti-seize on the threads of the plug. but i've never had it make a mess like that! ... i didn't put ANYTHING on the new plugs that went in...
 

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Bosche Platnum +4's are about 6 dollars each. The +2's are less though, probably closer to 3 dollars each, and it seems that for the minor cost difference, the engine running more smoothly and cleanly would take priority. The 1.8t is a bit odd on ignition, some people think sticking with Factory NGK's is best, but they are a bit on the pricy side.
 

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Discussion Starter #17
i always hear that the platinum plugs are bad for the turbos and that copper is what we should have...

??
 

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I always go with the OEM plugs for our cars. If you do a search, there have been people that had denso's fail on them prematurely. IMHO, not worth the savings.
 
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