Dear Tom and Ray: My husband insists that the white crud that he finds deposited on the spark plugs of my 1998 Camry are the result of using any gasoline other than his favorite brand. I do use name-brand gasoline, but I tend to stop at the most convenient station, rather than go out of my way for his brand. Am I as irresponsible as he thinks?
Ray: Tell your husband to get a life, Sherrill. That white crud shows up on spark plugs no matter what gasoline you use.
Tom: It's basically ash, sulfur and other unburned components from the gasoline that get deposited on the spark plugs over time. It can be made worse if you use a spark plug that's not hot enough, but I trust that your nit-picky husband has put the right plugs in your Camry.
Ray: But rest assured, that white crud is not doing any harm to your engine or your gas mileage. It's just that spark plugs do burn down and corrode after a while, and they build up deposits. That's why manufacturers recommend that we do what? Change them every so often.
Tom: And think about this, Sherrill: The differences between brand-name gasolines are so small that the companies have to lure you to their stations by advertising the cleanliness of their restrooms. We think that's as good a reason as any for choosing one brand over another.
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