How Odors Can Reveal Problems
The smell of burned toast
A light, sharp odor - often signals an electrical short and burning insulation. To be safe, try not to drive the vehicle until the problem is diagnosed.
The smell of rotten eggs
A continuous burning-sulphur smell that usually indicates a problem in the catalytic converter or other emission control devices. Don't delay diagnosis and repair.
A thick acrid odor
Normally means burning oil. Look for sign of a leak.
Smell of fuel vapors after a failed start
This usually indicates you have flooded the engine. Wait a few minutes before trying again. If the odor persists, chances are there's a leak in the fuel system - a potentially dangerous problem that requires urgent attention.
Burning resin or an acrid chemical odor
This might signal overheated brakes or clutch. Check the parking brake. Stop. Allow the brakes to cool down after repeated hard braking.
Light smoke coming from a wheel
Generally this indicates a jammed or stuck brake. The vehicle should be towed for repair.
A sweet, steamy odor
Typically this type of odor indicates a coolant leak. If the temperature gauge or warning light does not indicate overheating, drive carefully to the nearest service station, keeping an eye on your gauges. However, if the odor also has a hot, metallic scent (and you spot steam rising from under the hood) then your engine has probably overheated. Pull over immediately. To continue driving might cause severe engine damage. It's wise to have the car towed for repair. You can find helpful advice on reasons why head gaskets fail.