A strong gasoline smell under or around your car, a wet spot on the driveway, or a fuel gauge dropping faster than usual - those are all fuel leak signs. Gasoline is highly flammable and a leak near the hot exhaust can ignite. Park the car. Don't drive. Here's what to do.
Rubber sections of the fuel line crack with age and heat. Steel sections rust through, especially in salt-belt states. You'll see wet spots and smell gas. Replacement runs $150-400.
Diagnose My Leak →The O-rings and seals on each injector dry out and leak fuel onto the engine - dangerous because the engine is hot. Look for wet spots on top of the engine. $200-500 to reseal.
Diagnose My Leak →A bad gas cap doesn't leak liquid but lets fuel vapor escape - and triggers the dreaded P0455 / P0456 codes. New cap: $15-40. Always tighten until it clicks.
Diagnose My Leak →On many cars the fuel pump and filter are inside the gas tank. A failing seal at the top of the tank drips fuel onto the ground when the tank is full. $400-800 to replace.
Diagnose My Leak →Rust or impact damage can puncture the tank itself. The leak gets worse as the tank fills. Tank replacement is $600-1,200, or $200-400 for a professional patch.
Diagnose My Leak →Describe what you're seeing and our AI mechanic will tell you what it is, how serious it is, and what it costs to fix - in seconds.
Get My Free Diagnosis →No account needed. First answer is free. Full report is $5.99.
Fuel system leaks - especially vapor leaks (EVAP) - trigger these codes. P0455 / P0456 are extremely common and often just a loose gas cap.
No. Liquid gasoline near a hot exhaust or engine can ignite. Even fuel vapor can pool and ignite. Park the car outside, do not start it, and have it towed.
You may have a vapor leak rather than a liquid leak. Common causes are a loose gas cap, a cracked EVAP hose, or a failing purge valve. These trigger P0455 or P0456 codes - usually a $15-150 fix.
Gas cap: $15-40. Fuel line: $150-400. Injector seals: $200-500. Fuel pump assembly: $400-800. Fuel tank replacement: $600-1,200. Vapor system valves: $100-300.
A small fuel leak under the hood can run the engine fine but you'll smell gas at idle and stoplights. Common cause is a leaking injector O-ring or fuel rail seal. Get it fixed within days - it's a fire risk.
Tell our AI what you see under your car. You'll know what it is, whether it's safe to drive, and what the fix costs - in under a minute.
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