Spark plugs
Thread Starter
Melting Slicks
Joined: Mar 2008
Posts: 2,962
Likes: 254
From: Richmond, Ky
Spark plugs
These are platinum AC plugs that have been in the car for at least 40k miles and 14 years, probably longer. I was surprised they were in such good shape. It appears they were gaped at .060 which was recommended at that time. Wires were also at least that old and could have been the originals. Done as preventative maintenance, but was hoping I would be able to tell a difference in drivability which was negligible.
I have a slight hesitation on initial tip in of the throttle that I’d like to address but have no idea where to look for that specific issue. 99 FRC with 86,000 miles. Any help appreciated.
Moderator, Tech Contributor
Joined: Sep 2013
Posts: 15,498
Likes: 3,999
From: Cape Coral, Florida
Without a scan tool and sone diagnostic equipment you’ll only be guessing…can’t tell by looking at those plugs if that is why you posted them…could be fuel or even TPS or APP…were the plugs replaced and you still have some hesitation??
Thread Starter
Melting Slicks
Joined: Mar 2008
Posts: 2,962
Likes: 254
From: Richmond, Ky
Yes I replaced them as a maintenance decision along with the wires. They were in the car when I bought it 14 years ago and about another 40k since. I’m doing other maintenance issues and hoping to solve the throttle response issue along the way.
Safety Car
Joined: Mar 2017
Posts: 3,765
Likes: 938
From: Orlando Florida
Double check that the wires are securely attached to both the plugs and the coils. I know that reads poorly, but it can be difficult to verify secure connections and it can make a difference. Also make sure the air tube connections are good, no gaps or leaks. Any air getting in without going through the mass sensor messes with idle something terrible.
Thread Starter
Melting Slicks
Joined: Mar 2008
Posts: 2,962
Likes: 254
From: Richmond, Ky
Thanks for the replies. I’m going to be replacing the oil pressure sensor soon and I’m going to go the intake manifold removal route and will be examining vacuum lines and mass airflow condition ect. At some point once I have done what I know needs to be done, I’ll seek out some tuning help as I don’t have access to the equipment or the expertise to use it. The engine starts and idles fine, performance is acceptable but for a stock engine i think there is a little more to be gained.
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Thread Starter
Melting Slicks
Joined: Mar 2008
Posts: 2,962
Likes: 254
From: Richmond, Ky
The picture of the plugs are platinum plugs that were in the car when I got it. I’d say they are at least .060 but I also noticed the platinum pads were completely missing on some of them. The new plugs were pre-gapped at .040 but I still tweaked a couple.