We learn a lot about cars from friends, family, mechanics, and other drivers. Some advice is genuinely useful, but some “rules” come from a different era of automotive technology. Here are a few car myths that are still surprisingly common.
“You need to warm up the engine for a long time before driving.”
Modern cars generally don’t need to sit idling for many minutes before you start driving. After starting the engine, give it a short moment to stabilize, then drive gently until it reaches operating temperature. Avoid hard acceleration while the engine is still cold.
“More expensive fuel is always better.”
A higher octane rating doesn’t automatically mean better fuel for every vehicle. The right fuel depends on the engine and the manufacturer’s recommendations. Using a higher-octane fuel than required doesn’t necessarily make a car faster or more fuel-efficient.
“Engine oil must always be changed every 3,000 miles.”
This rule comes from an older generation of vehicles and maintenance practices. Modern engines and oils can often go much longer between oil changes. The correct interval depends on the vehicle, oil type, and driving conditions, so the manufacturer’s maintenance schedule is the best place to start.
“The number on the tire is the recommended tire pressure.”
Not necessarily. The number printed on the tire can refer to the tire’s maximum permitted pressure rather than the pressure recommended for your vehicle. For the correct pressure, check the vehicle manufacturer’s sticker or owner’s manual.
“An older car is automatically a worse car.”
Age alone doesn’t tell you everything about a vehicle. Maintenance history, mileage, mechanical condition, previous damage, and overall care can be much more important than the model year.
That’s why buying a car—especially at an auction—is about looking beyond a single number. A low price, a newer year, or a familiar brand doesn’t automatically make a vehicle the right choice. The details matter.
Car technology keeps changing, and some advice simply doesn’t age well. The smartest approach is to check the information against the specific vehicle you’re considering rather than relying on a rule you’ve heard for years.
What car myth have you heard the most?