How to Know If a Fuel Filter Is Dirty
- 1). Check your ignition system if your engine has difficulty starting. If the problem is not with the ignition system, this indicates that your fuel filter is dirty and is no longer able to filter fuel.
- 2). Pay attention to the performance of your engine, especially at high speeds. If the engine is sputtering, making any other unusual noises, this can indicate a dirty fuel filter.
- 3). Remove the fuel filter from your car. Hold it up and blow through, holding one finger behind the filter. If there is resistance, then the filter is dirty and needs to be replaced.
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