Spark plugs? Who needs 'em?

Dear Car Talk

Dear Car Talk | Dec 01, 1988

Dear Tom and Ray,
I have a 1986 Toyota and need an impartial opinion about maintenance. The manual indicates spark plugs should be changed at 30,000 miles. The question is, if the car is performing well, does it need new spark plugs?

TOM: We don't usually answer questions about performance, we direct those to Dr. Ruth. But since you've already wasted the stamp, you should know that you can't always tell whether a car is "performing" well unless you examine the spark plugs. Worn plugs can impede performance, reduce mileage, and increase pollution. These symptoms may not be perceptible to you if you drive the car every day. If you want my opinion, you probably do need plugs at 30K.

RAY: More importantly, the manual calls for much more than new plugs at 30,000. It calls for a new air filter, a new fuel filter, a cooling system flush, a complete brake inspection and more. You should go the whole nine yards.

TOM: Right, this is no time to be a cheapskate. Remember the famous Car Talk axiom: It's the stingy person who spends the most. Skimping on regular service can cost you a bundle later on. The maintenance schedules included in owners manuals are actually worth following and should be followed--with one important exception. The oil should be changed every 3000 miles regardless of how many zillion miles the manufacturer claims you can go between changes. So spend the money on the spark plugs and the complete 30,000 mile service, and next time you have a question about performance, write to a therapist, not a couple of meatballs like us.

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