Cleaning fuel injectors with transmission fluid and gasoline...?

Dear Car Talk

Dear Car Talk | Aug 01, 1991

Dear Tom and Ray:

I have a 1988 Ford Taurus. I told a friend that I was going to get my fuel injectors cleaned. He said to use a pint of transmission fluid in a tank of gas, which he has been doing for some time. Any comments?

TOM: How many horsepower does your friend's lawnmower have, Sam? This is one of those old wive's tales. We've never heard of an automaker that recommends dumping Automatic Transmission Fluid (ATF) in with the gasoline.

RAY: ATF does have some detergent properties, but who knows what else it might do to your fuel injectors? Fuel injectors cost many hundreds of dollars to replace, so they're not something you want to mess around with.

TOM: Our advice is to use a detergent gasoline every time you fill up, and change your fuel filter once a year. That should obviate the need for ever having to clean the injectors.

RAY: And if your injectors are already at a point where they need cleaning, there are products on the market specifically designed to do it. I'd use one of those, and leave the ATF in the transmission.

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