Calling all spark plug gurus...
Thread Starter
Racer
Joined: May 2009
Posts: 279
Likes: 4
From: Cincinnati OH
Calling all spark plug gurus...
I just replaced the plugs and wires in my stock 99 vert at 60K. The plugs that came out are marked AC 41-952 25321615. I believe they are original but not sure?
Pictures follow, and I am seeking to learn what I can about the condition of the engine based on the plugs that were removed.
There was a very occasional miss at idle only before the change. The idle miss has all but disappeared with new plugs/wires. My guess is the missing cathode from the cyl 4 plug was the cause of the miss.
I appreciate any insight you gurus can give.
Pictures follow, and I am seeking to learn what I can about the condition of the engine based on the plugs that were removed.
There was a very occasional miss at idle only before the change. The idle miss has all but disappeared with new plugs/wires. My guess is the missing cathode from the cyl 4 plug was the cause of the miss.
I appreciate any insight you gurus can give.
Melting Slicks
Joined: Oct 2007
Posts: 2,798
Likes: 8
From: It's true money can't buy happiness, but it is more comfortable crying in a Corvette than on a bicyc
St. Jude Donor '13
If you're only missing one you're doing good. I lost 4. I run the NGK plugs with no pucks.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
The miss most likely was a result of the excessive gap. It idle that becomes an issue. Most people who replace the OEM plugs marvel at how much better their car idles.
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Le Mans Master
Joined: Sep 2007
Posts: 7,604
Likes: 8
From: Belleville Il
Hell mine just flat did EVERYTHING better after new plugs and wires (Delco Iridiums at .040) But the ones that came out had gaps from mid .060s to mid .080s. I was amazed that it was running as good as it did!!
Those damn little pucks always fall off.
Thread Starter
Racer
Joined: May 2009
Posts: 279
Likes: 4
From: Cincinnati OH
I am thinking the original owner may have used the most "affordable" gasoline they could find.
I have only run premium in the four months that I have owned it.
I am wondering if I should take it to a tuner and ask them about possible richness?
It is 100% stock now, but I will be installing GHL bullet exhaust soon.
