What Can Make a Car Catch Fire—and How to Prevent It

A car can ignite due to fuel or oil leaks, electrical faults, overheated components, collisions, battery failures, arson, or environmental heat sources like hot exhaust contacting dry vegetation. While modern vehicles include safety systems to reduce risk, fires still occur when heat, fuel, and oxygen converge—often triggered by maintenance issues, defects, or crash damage. Here’s what typically causes vehicle fires, how they differ between gasoline and electric cars, the warning signs, and what to do if it happens.

The Most Common Ignition Sources

Car fires usually start when a hot surface or spark meets flammable material (fuel, oil, plastic, upholstery). The following are the most frequently cited causes by fire services, investigators, and safety regulators.

• Fuel system leaks: Gasoline or diesel dripping onto hot engine or exhaust parts can ignite quickly.
• Electrical shorts or overloads: Frayed wiring, corroded connections, or incorrect fuses can spark and ignite plastic insulation or nearby materials.
• Battery failures (all vehicles) and thermal runaway (EVs/HEVs): Internal faults or crash damage can trigger intense, persistent fires in lithium-ion cells; 12V batteries can also short and spark.
• Oil and fluid leaks: Engine oil, transmission fluid, and power-steering fluid can ignite on exhaust manifolds or catalytic converters.
• Overheated catalytic converters and exhausts: Contact with dry grass, leaves, or road debris can start fires under the vehicle.
• Overheated brakes, wheel bearings, or dragging brakes: Excessive heat can ignite nearby materials or cause tire fires.
• Tire blowouts and rim contact: A blowout at speed can generate sparks or heat that ignites rubber or nearby components.
• Crashes: Ruptured fuel lines, damaged batteries, and severed wiring can create sparks and fuel vapors in seconds.
• Aftermarket modifications: Poorly installed audio systems, remote starters, light bars, or performance parts can overload circuits and create shorts.
• Defective components under recall: Known issues (for example, ABS modules, fuel pumps, PCV heaters, block heaters) have prompted fire-related recalls—even when vehicles are parked.
• Arson or intentional ignition: Accelerants, flares, or fireworks can set vehicles ablaze quickly.
• Refueling errors: Spilled gasoline, running engines during refueling, or ignition sources near vapors can cause flash fires.
• Smoking materials and lighters: Discarded cigarettes or malfunctioning lighters can ignite upholstery.
• Environmental exposures: Wildfires, lightning strikes, or radiant heat from nearby burning objects can ignite a car.
• Charging equipment faults (for EVs/plug-in hybrids): Damaged cables, non-compliant chargers, or improper wiring can overheat connectors.

In most accidental cases, the chain of events starts with a small leak or electrical issue that goes unnoticed, builds heat, and finally meets an ignition source. Quick detection and maintenance are key.

Internal-Combustion vs. Electric Vehicles: How Fires Differ

Gasoline and diesel vehicles carry flammable liquids and emit heat through exhaust systems; their fires often start under the hood or underneath after a leak or electrical short. Electric vehicles store energy in high-voltage batteries. Available data so far suggests EVs do not catch fire more frequently per vehicle than internal-combustion cars, but when lithium-ion batteries do burn—typically after damage or a cell defect—fires can be harder to extinguish and may re-ignite. Fire departments often use large volumes of water for cooling batteries and may monitor vehicles after a thermal event.

Warning Signs Your Vehicle Could Ignite

Several sights, smells, and sounds may indicate a developing fire risk. Treat these as urgent and have the vehicle inspected immediately.

• Smell of gasoline, solvent, or burning plastic/rubber inside or around the car.
• Visible fluid drips under the engine or near the fuel tank; rainbow sheen or oily residue.
• Smoke or wisps from the engine bay, wheel wells, or undercarriage.
• Repeatedly blown fuses, flickering lights, or hot electrical connectors.
• Unexplained high engine temperature, overheating warnings, or misfiring.
• Clicking or buzzing relays, especially after shutdown; hot smell near the dash.
• For EVs/hybrids: error messages for high-voltage systems, hissing or popping from the battery area, strong sweet/solvent odors.
• Brakes dragging, burning smell after short drives, or wheels too hot to touch.

If you notice these signs, stop driving as soon as it’s safe, park in an open area away from structures, and seek professional help—small issues can escalate quickly.

What To Do If Your Car Is On Fire

If you see flames or heavy smoke, prioritize your safety and that of passengers and bystanders. The steps below reflect guidance commonly shared by fire authorities.

1. Pull over safely: Signal, move to the shoulder or an open area, stop, and set the parking brake.
2. Shut it down: Turn off the engine and, for EVs/hybrids, power down and exit the vehicle; remove the key or move the fob far from the car.
3. Evacuate immediately: Get everyone out, move at least 100 feet (30 meters) upwind, and keep others back.
4. Call emergency services: Dial your local emergency number and report the location and whether you see flames or smoke.
5. Do not open the hood or trunk: Introducing air can intensify the fire; components can explode.
6. Use an extinguisher only if it’s small and safe: A Class ABC extinguisher can knock down minor fires from a distance. If unsure, wait for firefighters.
7. Warn traffic: If safe, place hazard triangles/flairs far behind; avoid standing in traffic lanes.
8. For EVs: Assume high-voltage components are energized; do not touch orange cables or the battery pack.

Vehicles can reignite, roll, or explode tires and struts as heat builds—maintain distance until firefighters declare the scene safe.

Prevention and Maintenance Tips

Most vehicle fires are preventable with timely maintenance and safe habits. The following practices reduce risk across gasoline, diesel, and electric vehicles.

• Fix leaks immediately: Address any smell of fuel or evidence of oil/fluid drips.
• Follow maintenance schedules: Replace worn hoses, belts, and spark/plugs; keep cooling systems healthy.
• Use correct fuses and wiring: Never upsize fuses to stop them blowing; avoid overloaded accessory circuits.
• Professional installs: Have aftermarket electronics and towing wiring installed by qualified technicians.
• Heed recalls: Check your VIN at official recall sites and complete recall work promptly, especially for fire-related notices.
• Keep the engine bay clean: Remove leaves/debris that can contact hot parts; ensure shields and splash guards are intact.
• Mind where you park: Avoid tall dry grass that can touch hot exhaust or catalytic converters.
• Safe refueling: Shut the engine off; avoid using lighters/phones at the pump; clean up spills.
• Don’t smoke in the vehicle: Upholstery and trim ignite more easily than many realize.
• Brake and tire care: Prevent dragging brakes; keep bearings lubricated; maintain proper tire pressure.
• EV charging safety: Use certified equipment on dedicated circuits; inspect cables and connectors; avoid damaged or counterfeit chargers.
• Carry a small ABC extinguisher: Store it securely and know how to use it; it’s for early, small fires only.

Good maintenance and a cautious approach to heat, electricity, and flammable fluids are your best defenses against a vehicle fire.

Arson vs. Accidental Fires

Investigators distinguish between accidental fires (mechanical/electrical failures, collisions) and intentional ones. Arson typically shows multiple ignition points, use of accelerants, or entry damage. If arson is suspected, preserve the scene, avoid contaminating evidence, and contact authorities and your insurer.

Insurance and Legal Considerations

Comprehensive auto insurance generally covers fire damage, whether accidental or intentional (arson), minus your deductible. Document the incident with photos if safe, provide the fire report, and notify your insurer promptly. If a defect is involved, you may also have recourse through warranty or recall remedies. Never continue driving a vehicle with known fire-related recalls or warnings.

Where to Learn More

Safety guidance and recall information are maintained by recognized authorities. The resources below can help you stay current and reduce risk.

• National Highway Traffic Safety Administration (NHTSA): Check open recalls using your VIN and report safety issues.
• National Fire Protection Association (NFPA) and local fire departments: Vehicle fire safety tips and response guidance.
• Your vehicle’s owner’s manual: Manufacturer-specific warnings and emergency procedures (including EV/hybrid high-voltage safety).
• Your insurer or broker: Coverage specifics and claims steps for fire incidents.

Regularly reviewing these resources and acting on their guidance is a practical way to prevent fires and respond effectively if one occurs.

Summary

Cars catch fire when heat and sparks meet flammable materials—most often from fuel or fluid leaks, electrical faults, overheated components, collisions, battery failures, or arson. Maintain the vehicle, fix leaks, respect recalls, use safe charging and wiring practices, and react quickly to warning signs. If a fire starts, get everyone out, move away, call emergency services, and avoid opening the hood. These steps drastically cut the risk of injury and damage.