Why Cars Catch Fire: Causes, Warning Signs, and What to Do

Cars most often catch fire because heat, fuel, and oxygen converge after a failure—typically a fluid leak onto a hot surface, an electrical short, or crash damage. Both gasoline/diesel vehicles and electric vehicles can burn, though the triggers and fire behavior differ. Here’s what causes vehicle fires, how to spot early warning signs, and the steps experts recommend to stay safe and reduce your risk.

How Vehicle Fires Start

Any vehicle is a dense mix of heat sources, flammable materials, and high-energy electrical systems. When a defect, wear-and-tear, or collision compromises those systems, ignition can occur. Investigators frequently cite mechanical failures (like leaks) and electrical malfunctions as leading causes, with most fires originating in the engine bay, wheel/brake area, or near the exhaust.

The Most Common Triggers

The following list summarizes the factors most often associated with vehicle fires, based on patterns documented by fire investigators and transportation safety agencies.

• Leaking fluids on hot components: Gasoline, engine oil, power steering fluid, transmission fluid, and brake fluid can ignite if they drip onto exhaust manifolds, catalytic converters, or turbochargers.
• Electrical faults: Chafed wiring, corroded connectors, loose battery terminals, alternator failures, and improper aftermarket wiring or oversized fuses can cause shorts, arcing, and heat buildup.
• Overheating parts: Overworked brakes, seized wheel bearings, or clogged cooling passages can overheat and ignite nearby materials. A failing catalytic converter can run extremely hot and ignite underbody debris or dry vegetation.
• Crash damage: Collisions can rupture fuel lines, damage batteries, or pinch wiring, creating sparks near flammable vapors or compromised components.
• Poor maintenance: Ignored leaks, missing heat shields, neglected recalls, or infrequent inspections increase fire risk over time.
• Manufacturing defects/recalls: From ABS modules that can short to high-voltage battery defects in specific EV models, some issues have prompted “park outside” or repair-now notices in recent years.
• Human factors: Arson, smoking materials, or carrying/handling flammables (fuel cans, solvents, aerosol cans) in the cabin or trunk can lead to ignition.
• External hazards: Parking over tall dry grass can ignite vegetation via a hot exhaust; wildfires can also engulf parked vehicles.

While any single factor can be enough to start a fire, risk rises when multiple issues overlap—for example, an electrical short in a poorly maintained vehicle that also has oil seepage near a hot exhaust.

Where Fires Typically Begin

Location matters for both cause and response, and these are the areas investigators most often identify as origins.

• Engine compartment: The most common origin due to fuel, oil, and intense heat near ignition sources.
• Wheel/brake area: Stuck calipers, dragging brakes, or failed wheel bearings can overheat and ignite.
• Underbody and exhaust: Hot exhaust components can set fire to road debris or dry vegetation.
• Passenger cabin: Less common, but possible from smoking materials, faulty seat heaters, or wiring faults.
• Battery pack area (hybrids/EVs): Damage, defects, or internal failures can trigger thermal runaway within cells.

Knowing typical origins helps drivers recognize early warning signs—like a burning smell from the vents (engine bay) or smoke near a wheel (brakes/bearing).

Special Considerations for EVs and Hybrids

Electric and hybrid vehicles introduce high-voltage battery systems with different fire dynamics. Overall incident rates appear lower than for gasoline vehicles on a per-mile basis in many datasets, but when lithium-ion batteries do fail, suppression can be more complex and reignition is possible hours or days later.

The points below highlight EV/hybrid-specific risk factors and behaviors that differ from traditional vehicles.

• Battery thermal runaway: Internal damage, manufacturing defects, or severe overheating can trigger a chain reaction in battery cells that is difficult to extinguish.
• Delayed ignition and reignition: After a crash or saltwater immersion, a high-voltage pack may ignite much later; even after suppression, rekindling can occur.
• Charging-related issues: Faulty charging equipment, damaged connectors, or improper installations can cause localized electrical fires.
• Pack integrity and cooling: Coolant leaks inside some battery designs, or compromised pack enclosures, can contribute to failures.
• Isolation and safety systems: Modern EVs are designed to isolate high voltage in a crash, reducing shock risk—but responders still treat orange high-voltage cables and the pack as “do not touch.”

For drivers, the most practical EV differences are: follow manufacturer charging guidance, keep software up to date, and seek inspection if the vehicle has been flooded, physically damaged, or shows battery-related warnings.

Warning Signs Before a Car Fire

Many vehicle fires are preceded by smells, sounds, smoke, or warning lights. Early action can prevent escalation.

• Smells: Burning plastic or insulation, raw fuel, or acrid smoke from vents or under the hood.
• Visible smoke or steam: Smoke from wheel wells or underbody; wisps from the hood; persistent steam mixed with a sweet smell may indicate coolant, but smoke suggests something else is burning.
• Electrical symptoms: Repeatedly blown fuses, flickering lights, hot-to-the-touch charging cables or power accessories, or a battery/alternator warning light.
• Overheating and performance changes: Temperature gauge spiking, loss of power, rough running, or strong brake smell from a single wheel.
• Fluid leaks: Oily residue or drips near the engine/exhaust; puddles with a fuel odor.
• EV/hybrid alerts: High-voltage system warnings, rapid state-of-charge anomalies, hissing or popping from the battery area, or unusual odors while charging.

If you notice these signs, pull over safely, shut the vehicle down, and investigate from a safe distance. It’s better to call for assistance early than to risk a developing fire.

What to Do If Your Vehicle Smokes or Catches Fire

Safety experts recommend clear, quick actions to protect people first and prevent the fire from intensifying.

1. Signal and pull over safely: Stop away from traffic if possible. Shift to Park (or Neutral with parking brake), and turn wheels toward the curb if on a grade.
2. Shut it down: Turn off the ignition or power the vehicle down to cut fuel and electrical flow. If charging, hit the emergency stop at the station rather than unplugging a burning connector.
3. Evacuate immediately: Get everyone out, move 100–150 feet (30–45 meters) upwind, and keep a barrier (guardrail, ditch) between you and the vehicle if you can.
4. Call emergency services: Provide location, vehicle type (gas, diesel, hybrid, EV), visible flames or smoke, and whether hazardous cargo is present.
5. Do not open the hood or trunk fully: A rush of oxygen can flare the fire. If trained and the fire is very small, use a Class ABC extinguisher from a safe distance, aiming at the base of the flames, then back away.
6. For EVs/hybrids: Do not cut orange high-voltage cables or touch the battery pack. Expect possible reignition and keep your distance even after the fire looks out.
7. Keep others away: Do not reenter the vehicle for belongings. Warn oncoming traffic if safe to do so and wait for firefighters.

If the fire grows, prioritize distance and clear information for responders—modern vehicles can burn intensely and produce toxic smoke.

How to Reduce Your Risk

Regular maintenance and a few habits greatly reduce the likelihood of a vehicle fire.

• Fix leaks promptly: Address fuel, oil, and power-steering/transmission leaks; replace missing heat shields.
• Protect your electrical system: Use correct fuses, repair frayed wiring, ensure solid battery connections, and avoid overloading power outlets.
• Be cautious with aftermarket add-ons: Have remote starters, audio systems, light bars, and inverters installed by qualified technicians.
• Maintain brakes and bearings: Watch for dragging brakes or wheel noise and service promptly.
• Check for recalls: Run your VIN through your national safety agency or manufacturer site and complete recall repairs without delay.
• Keep bays clean and clear: Remove leaves/debris from the engine bay and underbody; don’t park on tall dry grass.
• Handle flammables safely: Don’t smoke in the car; avoid carrying fuel cans or solvents inside the cabin; secure cargo so it can’t rub or leak.
• EV/hybrid specifics: Use certified charging equipment, avoid damaged cables, install home charging to code, apply software updates, and have flood- or crash-exposed vehicles inspected before use.
• Carry basics: A small ABC extinguisher, triangle/reflective vest, and a phone charger can help you respond early and safely.

Focusing on leaks, wiring integrity, and recall compliance addresses the bulk of preventable fire risks for both combustion and electric vehicles.

Expert Context and Data

Fire service analyses in recent years consistently attribute most highway vehicle fires to mechanical failures and electrical malfunctions, with crash-related fires representing a smaller share. For EVs, current datasets suggest lower incident rates than gasoline vehicles on a per-mile basis, but battery fires can be harder to suppress and may reignite. Fire departments commonly use large volumes of water for cooling in EV battery incidents and may monitor the vehicle for an extended period afterward. Regardless of powertrain, prevention and early detection remain the most effective protections.

Summary

A car typically catches fire when a failure lets heat meet fuel in the presence of oxygen—most often from fluid leaks onto hot parts, electrical shorts, or crash damage. Watch for smells, smoke, and warning lights; pull over and shut down at the first sign of trouble; evacuate and call for help; and do not open the hood fully or handle high-voltage components. Regular maintenance, careful electrical work, and adherence to recalls greatly reduce the risk for both conventional and electric vehicles.

What is the most common car to catch fire?

Hybrid cars have the highest fire risk per 100,000 vehicles sold, followed by traditional gasoline-powered cars. While individual models like the Jaguar I-Pace and older Hyundai and Kia models had specific issues, the overall data indicates that hybrid vehicles are significantly more prone to fires than electric or gasoline cars.
 
Statistics by Vehicle Type 

• Hybrid Cars: Opens in new tabThe most fire-prone type, with around 3,475 fires per 100,000 vehicles sold.
• Internal Combustion Engine (ICE) Cars: Opens in new tabHave a lower risk than hybrids, with approximately 1,530 fires per 100,000 vehicles sold.
• Electric Vehicles (EVs): Opens in new tabHave the lowest fire risk, with only about 25 fires per 100,000 vehicles sold, according to a recent study.

Factors Contributing to Fires

• Hybrid and Gas Car Fires: Opens in new tabThe primary causes are issues related to fuel leaks, electrical shorts, and problems with components like anti-lock braking systems (ABS). 
• Electric Car Fires: Opens in new tabThe main risk for EVs is their batteries. While less frequent, these fires can be intense and difficult to extinguish. 

Why the Perception Differs 

• Over-Reporting of EV Fires: Opens in new tabDespite being rarer, EV fires are often more publicized and heavily reported in the news, leading to a perception that they are more common than they are.
• Under-Reporting of Gas Car Fires: Opens in new tabMost fires in traditional gasoline-powered cars do not make the news, so the actual number of fires is often underestimated.

What is the most common cause of car fires?

The most common causes of car fires are fuel system leaks, where flammable liquids ignite from a spark or hot engine component, and electrical system failures, which can cause sparks from faulty wiring or components. Poor vehicle maintenance can lead to both of these issues, increasing the risk of a fire from damaged wires or leaking components. 
Causes of Car Fires

• Fuel System Leaks: Flammable liquids like gasoline can leak from damaged lines or components and contact a hot engine part or a spark, leading to ignition. 
• Electrical System Failures: Worn or damaged wiring, short circuits, or faulty components can create sparks or heat, igniting nearby materials. 
• Poor Maintenance: Neglecting regular maintenance can result in damaged electrical wires, leaky fuel lines, or engines that overheat, all of which are fire hazards. 
• Engine Overheating: Overheating can cause fluids to spill and come into contact with hot engine components or wires. 
• Car Accidents: A collision can cause damage to the fuel tank, fuel lines, or electrical systems, leading to leaks, sparks, and potential ignition of flammable liquids. 
• Catalytic Converter Issues: A damaged or improperly functioning catalytic converter can become extremely hot and pose a fire risk if it contacts foreign objects. 

Prevention

• Perform Regular Maintenance: Have your car inspected and serviced regularly to catch potential problems with the fuel and electrical systems. 
• Be Vigilant for Leaks: If you smell gasoline or see fluid leaks under your car, get it checked and fixed immediately. 
• Address Electrical Issues: Don’t ignore warning signs of electrical problems, such as flickering lights or other malfunctions. 

What would make a car set on fire?

Cars catch fire due to a combination of flammable fluids (like fuel or oil), an ignition source (such as a spark from a damaged electrical system or a hot exhaust), and the presence of oxygen. Major causes include faulty fuel and electrical systems, engine or exhaust overheating, and mechanical or manufacturing defects, often accelerated by a lack of proper vehicle maintenance or by accidents that damage critical components. 
Common Causes of Car Fires

• Fuel System Issues: Leaks from damaged or poorly routed fuel tanks, lines, or injectors can release flammable gasoline, which can ignite from a spark or hot surface. 
• Electrical System Failures: Exposed or damaged wiring from wear, accidents, or even rodent damage can short-circuit and create sparks, igniting fuel or other nearby materials. 
• Overheating: An engine can overheat from a lack of coolant, an engine oil leak, or a failing water pump. The exhaust system, especially the catalytic converter, can also become extremely hot and ignite flammable debris or fluids that come into contact with it. 
• Mechanical Failures: Issues with components like a faulty battery, worn hoses, or other mechanical defects can lead to leaks or sparks that start a fire. 
• Defects and Debris:
  • Design/Manufacturing Defects: Faults in a vehicle’s design or manufacturing process can create inherent risks for fire, such as faulty ground bolts or wiring issues, as seen in some recalled vehicles. 
  • Flammable Debris: Accumulation of oily rags, spilled fluids, or dry vegetation under the vehicle can increase the risk of fire if they come into contact with a heat source. 
• Accidents: Crashes can rupture fuel lines and tanks, damage electrical systems, or damage engine components, leading to leaks and sparks that can quickly ignite. 
• Poor Maintenance: A lack of regular vehicle maintenance is a frequent human-caused factor, as it contributes to the development of leaks, worn wiring, and other mechanical issues that can lead to fires. 

This video explains the common causes of car fires: 1mBig QuestionsYouTube · Mar 8, 2025
Preventing Car Fires

• Perform Regular Maintenance: Follow your vehicle’s recommended maintenance schedule to address issues like fluid leaks, wiring problems, and engine overheating early. 
• Check for Leaks: Be vigilant for puddles of oil, coolant, or fuel under your car, especially after an oil change. 
• Inspect Wiring: Periodically check under the hood and dashboard for any signs of cracked or damaged wiring. 
• Address Warning Lights: Pay attention to dashboard warning lights, especially those related to temperature or fuel. 
• Be Aware of Odors: Promptly investigate unusual smells, such as burning rubber or metal, which could indicate a developing fire hazard. 
• Report Recalls: Respond to manufacturer recalls for potential design or manufacturing defects that could lead to a fire. 

Why would a car get caught on fire?

Usually cars catch fire due to the exposure of flammable liquids (such as gasoline) to surfaces hot enough to ignite them. This might be the exterior of a running engine, especially one which is damaged, or simply the sparks produced by forceful contact between steel or iron within a collision.