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Spark plugs covered in black gunk after 3 months

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jmatyas

10+ Year Contributor
198
0
Mar 13, 2009
Chattanooga, Tennessee
I have been having this terrible problem with hesitation for the longest time and ive tried everything to fix it. I read up on alot of things so i decided to go out and buy new spark plugs and plug wires again to see if there would be any change.

After pulling the plugs i found them covered in black dry goup. i really have no other way to describe it. like a heavy carbon coat. I think i may be running rich but i dont think that would cause my car to hesitate would it?

PLEASE HELP!!!! I bought my car in october of last year....and ive only drove it 3 weeks without it breaking again and again...
 
My guess is the spark plug well seals are leaking. There are seals between the valve cover and the head around the spark plug wells, and if they were leaking then oil could slowly get in the wells. I'm surprised all of them are covered though. Is your valve cover torqued to spec on all the bolts?
 
I was about to put in a new valve cover but i didnt want to spend the $50+ for one and that not be it. I was just looking for a 2nd oppinion before i went out and bought one. If i did buy one it will be powdercoated blue for sure!!!! LOL.

The left 2 spark plugs had it the worst. The other 2 were not as bad.
 
Nice I'll have to do that soon. Is there anything specific I should know before I start or is it just a take off, clean, prep, gasket, cover, torque wrench apr bolts? LOL. Sorry for the random line but hey I'm still kinda new to imports. :)
 
While you are in there replace that half moon seal at the end of the exhaust cam, part # MD372348. Use some black RTV for the curved section, and you will never have to replace that again. Dont use air tools to tighten those VC bolts, as our covers are very prone to cracking. I use a ratchet wrench and tighten them just a tid bit past snug, they should have lock washers on the bolts to prevent them from backing out. I replaced all of my bolts with new ones from Mitsu, cost me about $10 for all of them.
 
Hey ive been looking all over about that half moon piece your talking about and cant seem to find a really good link to show how its installed or what exactly it is. Could you please explain it a lil bit more. I'm sorry to look like a noob but hey we all start somewhere right LOL. Also you mentioned RTV. What does that stand for?
 
I had a problem with excessive carbon deposits on my plugs. Did a little research and found out I had the wrong plugs in there. Make sure you're using NGK coppers, in the correct heat range and properly gapped. Reminds me about the time I pulled my plugs for inspection and I dropped one of the plugs. Didn't think much about it and re-installed them. Car hesitated to freakin' hell. Eventually found that I bent the tip on the one I dropped, re-gapped the plug and was all good again.
 
Sadly every place out here does not carry NGK anymore. WHICH IS STUPID :(. But they told me that the DENSO platnum tt's replaced them.... well of course i bought them trusting the friendlies at auto zone but well see. Just replaced them yesterday and havent been able to start my car yet because of an ignition issue. I swear my car will never stay running.
 
I also have a hard time finding the NGK bpr6es. The only place I've been able to purchase them are from the online dealers. The problem with carbon deposits I mentioned earlier, I was using the NGK iridiums that were "recommended" by the guy behind the counter. In the end I think those guys are trying to make a sale but you do find very helpful people who know what they're talking about now and then.

BTW, what ignition issues do you have? Good luck with them!
 
I thought it was my starter at first, had that replaced and the old one tested. Both passed A+. sigh... so it wasnt the starter. Next im replacing the battery with an optima red top tomorrow :). weather it helps or not hell its an optima finally. LOL. The issue im having is ill try to start and you hear it click and actuate but not crank over. Had the battery tested and its on its last leg. Once i put it in tomorrow ill know for sure its more money than i thought. But I have noticed now that i went out and looked alot closer I do have a small oil leak out the side of my valve cover so its time to change that too.
 
Just a thought, but if you have been having problems starting the car, I would check and make sure your timing is all in tune. I was having starting problems, and in the ladder of the situation found out my balance shaft belt was tore up, and my intake valves got trashed. Head Re-Build! Just a thought for ya to check over.
 
I just realized that from your vague post I might have mistakenly thought you were talking about goop in the plug wells and you might have meant on the plug tips. Where exactly is the black goop?

The platinums most likely won't work for you. If you're looking for NGK BPR7es or 6es plugs try a motorcycle shop. That's where I get mine, for cheaper than the performance shops since those like to jack up the prices.
 
Black goop looks like heavy coated sludge that has dried. Kind of a full black coat on the threads and the spark area itself.

Also anyone know where i could get a powdercoated candy blue 4g63 valve cover for a good price? need one asap
 
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