Poor Fuel Economy
Urgency: LowA sudden or gradual decrease in fuel efficiency can indicate several issues. Common causes include a dirty air filter restricting airflow, faulty oxygen sensors providing incorrect fuel mixture data, worn spark plugs causing incomplete combustion, or tire pressure issues. Fuel economy that drops by more than 10-15% warrants investigation.
Need to read your codes?
An OBD-II scanner lets you read and clear diagnostic trouble codes from your vehicle's computer. Most scanners work with any car made after 1996.
Browse OBD-II Scanners on AmazonPossible Causes
- Dirty or clogged air filter
- Faulty oxygen sensor
- Worn spark plugs
- Low tire pressure
- Dirty fuel injectors
- Thermostat stuck open
Related OBD-II Codes
When to See a Mechanic
If fuel economy drops suddenly, have it checked soon. Gradual decline can be addressed at your next regular service.
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