How do those spark plugs look?
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
I change oil in all our vehicles every 3K miles. If it's down more than 1/2 qt at the change, something's wrong. Haven't had my latest Vette long enough to know how it holds up in this respect, but I've been going by the 1/2 qt rule more than 30 years. Every vehicle that's used more has either fouled the plugs with oil or leaked it in the driveway.
Anyway, if you change your plugs and the miss goes away, even temporarily, you'll know the problem isn't electrical in nature.
Anyway, if you change your plugs and the miss goes away, even temporarily, you'll know the problem isn't electrical in nature.
I'll try the plugs when I'll get home and will also check the timing to make sure I'm at 36 degrees total timing..
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
Update. Changed out the plugs and no change.. Then I went to check the timing and when I checked my idle timing, I knew immediately that there was a problem.. Idle timing was at 23 degrees 
Backed off the timing to 13 degrees at idle and test drove the car.. Drove a lot better.. Went back and checked total timing and I was still at 39 degrees, so I backed it off to 36 degrees total timing which resulted in 11 degrees idle timing.. Test drove it again and it's now 90% better than it was.. It's still not perfect but it may be that I got some bad gas in it.. Since in went to WAWA and put 92 octane into the car, I noticed a difference.. I usually run Shell or Costco 93 octane gas which the car likes a lot.. I'll go back to Costco after that tank and I bet that the car will run 100% perfect with better gas. There is still a little "hole" where the car doesn't pull too well between about 3000 and 3500 RPM but above 3500 RPM, it pulls really hard and feels stronger than ever.
Backed off the timing to 13 degrees at idle and test drove the car.. Drove a lot better.. Went back and checked total timing and I was still at 39 degrees, so I backed it off to 36 degrees total timing which resulted in 11 degrees idle timing.. Test drove it again and it's now 90% better than it was.. It's still not perfect but it may be that I got some bad gas in it.. Since in went to WAWA and put 92 octane into the car, I noticed a difference.. I usually run Shell or Costco 93 octane gas which the car likes a lot.. I'll go back to Costco after that tank and I bet that the car will run 100% perfect with better gas. There is still a little "hole" where the car doesn't pull too well between about 3000 and 3500 RPM but above 3500 RPM, it pulls really hard and feels stronger than ever.
Last edited by GrandSportC3; Jan 1, 2016 at 03:04 PM.
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
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Team Owner
Joined: Jul 2001
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
Actually, it did't smoke at all.. Not sure where all the oil went.. it was very strange..
Car ran great otherwise.. it was actually a 383 engine that I had in a 69 Vette that I owned around 1998.. Great power but high oil consumption.
Car ran great otherwise.. it was actually a 383 engine that I had in a 69 Vette that I owned around 1998.. Great power but high oil consumption.
Last edited by GrandSportC3; Jan 1, 2016 at 03:42 PM.
Thread Starter
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Joined: Jul 2001
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
Team Owner
Joined: Apr 1999
Posts: 21,953
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From: Reno Nevada
2024 C3 of the Year Finalist- Modified
Thread Starter
Team Owner
Joined: Jul 2001
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
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From: Crossville TN
With a stock ignition coil, the gap on your spark plugs should be set at .035". Setting them at .040" or higher will result in some spark miss at lower RPMs and will be particularly noticible with WOT at lower RPMs. Hopefully, you re-gapped the new plugs to .035".
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From: Lakeland, FL
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St. Jude Donor '03, '06, '17
The new Platinum plugs are gapped .035 out of the box..