Spark plugs

1989 OLDSMOBILE DELTA 88
200,000 MILES • 6 CYL • FWD
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KHOLDER
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  • 4 POSTS
How do i determine by looking at spark plug if it has gone bad or fouled.
May 15, 2011 at 3:46 PM
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PROTECH1980
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  • 901 POSTS
Check this link, it will assist you with pictures: http://www.gnttype.org/techarea/engine/plugs.html
May 15, 2011 at 4:08 PM
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FIXITMR
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  • 9,990 POSTS
if it's firing, the post and tip will be dry even if it's not especially clean looking. if not firing it will be darkish and damp/wet. the most common fault with newer cars since 80's is plug just wears out. tips and posts wear down and this changes gap. look at all plugs as a group to find a problem with 1 or more. mark which cylinder each came from to determine if off color/dead plug indicates cylinder itself has a problem with air/spark/compression/fuel.
May 15, 2011 at 4:24 PM
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