Are these spark plugs new or used?
Spark plug wear is judged by electrode erosion, gap widening, and deposit buildup rather than just clean appearance. Telling a new plug from a high-mileage one requires checking for rounded center electrodes and heavy carbon or ash fouling, which prevents proper ignition and misfires.
What people tried
Every workaround mentioned in the threads below. We haven’t tested any of them — and nobody here is claiming they worked.
- 1Visual inspection of the spark plugs
- 2asking mechanics online for advice
- 3replacing the spark plugs based on appearance
In their words
Unedited, most upvoted first, each linked to the thread it came from.
Where this came up
People with this problem also raised
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