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First off, I am never going to let anyone change my spark plugs again except me.

About 10K miles ago (I'm at 13K now) I had a local dealer (performance shop also) put my 2.75 upper on my car and change my spark plugs to teh NGK TR6's...now I gave them specific directions to gap them at .035". They must of of ignored my request and gapped them totally wrong.

Foward to present time now. Yesterday I decided to change my spark plugs myself. I gapped them at .035" and begin the change. As I was taking each of the old spark plugs out I checked the gap on them. ALL OF THEM WERE FROM .041-.043 ONE WAS EVEN .045!!!!!!!

I don't know if it was my fault for not checking them in 10K miles or if the installer mentioned above screwed up the gap entirely.

To top it off all my spark plugs had very dark black sut on them. ALL OF THEM. What does this mean? I can't see it being a rich condition because the last time I went to the dyno I was at 11.8:1 almost all the way across the board (tail pipe sniffer).

Anyways, car is running a MILLION times better then before...I think the horrible gapping hurt me badly before.
 

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The Ubiquitous Jimmy V.
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10k miles on plugs to find gap opened a little is normal..
 

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Well, there is also a good possibility that they used a coin gapper *GASP* and heaven's forbid! I've found that a coin gapper, aside from easily able to damage your plugs, normally shows about .005 to .010 off versus a true gap with a set of feeler gauges and an electrode point bender.

Sincerely...
 

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The Ubiquitous Jimmy V.
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RWTD said:
Well, there is also a good possibility that they used a coin gapper *GASP* and heaven's forbid! I've found that a coin gapper, aside from easily able to damage your plugs, normally shows about .05 to .10 off versus a true gap with a set of feeler gauges and an electrode point bender.

Sincerely...
Good Point
 
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