Some weeks ago you settled or perhaps escalated a marital...

Dear Car Talk

Dear Car Talk | Jun 01, 1994

Dear Tom and Ray:

Some weeks ago you settled (or perhaps escalated) a marital dispute about the benefits (or lack there-of) of buying high octane gasoline. Now how about tackling a related marital dispute: Are those fuel injector cleaners on the market beneficial? If so, how often should you use them? Are they the same thing as the detergent additives in some brands of gasoline? If you use gasoline with these additives, do you still need to use fuel injector cleaner? Thanks.

TOM: Wow, what a great question, Sherri! The simple answer is no, you don't have to use a fuel injector cleaner.

RAY: The gas companies spend lots of money telling us how great their detergent gasolines are, and that if you use them, you'll never have clogged fuel injectors.

TOM: And then, sitting right next to the pumps, are big bottles of the fuel injector cleaner made and sold by the same gas companies! Interesting, isn't it? It's like the moving company assuring you that they never break anything, and then urging you to buy their optional insurance "just in case."

RAY: In the old days, only premium gas had detergents to protect fuel injectors. But now that most cars on the road are fuel injected, all grades of gasoline have these detergents. So unless you're filling up at Fred and Ethyl's Gas-A-Rama and Charm School, you can leave the bottles of fuel injector cleaner sitting on the rack.

TOM: Rather than spending your money on fuel injector cleaners, spend the money on a new fuel filter every year. That's the single best thing you can do to protect your injectors.

RAY: And if you have an older, fuel injected car that ran for a long time on gasoline without detergents, and your mechanic suspects the injectors are causing it to run poorly, then you can try some fuel injector cleaner. The stuff does work, but it's not necessary to use it for preventive maintenance, and I think that's what you want to know, Sherri.

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