Engine Oil on Sparkplug Threads - Misfiring / Hesitation


New Member
Dec 25, 2018
Alexandria, VA
Hi everyone! This is my first post in this forum. I have been lurking and reading for a while and you have all helped me with my project.

I was checking all my spark plugs the other day and on spark plug # 1 there was oil on the threads and build up on the electrode. I got worried and checked all of the other ones and found oil only on the threads of the others. The other spark plugs had a little bit of black on the side electrode but no buildup or gunk of any sort that would be blocking it. My car was mis firing a few days ago and found this to be a broken distributor wire on #4. I cleaned off all the oil on the spark plugs and put them back in, put new wires in, and fixed the gaps on all the plugs to see if the car was still misfiring or hesitating. Luckily the car stopped mis firing and has not any more since last week. The car is still hesitating on slow acceleration but I think this might have to be something on the carburetor? Im new to this, should I take apart the engine and replace the piston valve seals or something else inside, or should I wait to see if more oil builds up and after I have my carb looked at/fixed?


PS - The car I own is a 1969 Coupe 302ci V8 - with a Holley 4 BBL Carb which still needs to be tuned
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15 Year Member
Nov 18, 2002
Cape Cod, Ma.
Oil on the plug threads is probably from the valve cover, not from inside the engine. How about starting with a fresh tuneup, plugs, points, condenser, rotor, cap, wires. New filters . Set the dwell and the timing, adjust the carb and see what you have.
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