Nine things almost every driver believes about cars, and what each one quietly drains from your wallet. The last is the most expensive thing on the list.
Carburettors needed a long idle. Fuel injection does not: about 30 seconds is enough. Idling burns fuel at zero miles per gallon and heats the engine slower than gentle driving.
Octane measures resistance to knock, not power or cleanliness. If the manual says regular, premium adds nothing but a bigger number at the bottom of the receipt.
It was written for oils that no longer exist. Most modern cars go 5,000 to 10,000 miles between changes. The manual, or the car's own oil-life monitor, gives the real figure.
The pressure moulded into the tyre is its maximum, not your car's target. The correct figure sits on a sticker inside the driver's door frame, and it is usually much lower.
Around town, open windows are the cheaper way to stay cool. At highway speed the drag they add costs more fuel than the compressor does, so closing up saves money.
No quote form has a field for paint. Premiums come from the model, engine, repair cost, your record and where you park it. A red car and a grey one rate identically.
Squeezing in extra fuel after the shut-off can push liquid into the vapor-recovery canister, a part that costs hundreds to replace. You gain a few cents of range.
Federal warranty law bars a carmaker from tying your coverage to dealer servicing. Use the garage you trust, keep the receipts, and the warranty stands.
Every plug-in sold in the US carries a battery warranty of at least eight years or 100,000 miles, and California demands more. Most packs are still healthy well past it.
Almost every myth here is settled by the manual in your glovebox. Read it once and you stop paying for advice that expired decades ago.