Smoke coming from under the hood

Symptoms

• Visible smoke rising from the engine bay, seen through the hood vents or grille
• Smoke may be white, gray, or black depending on the source
• Sometimes accompanied by a burning smell (oil, plastic, or coolant)
• Engine may or may not show performance changes alongside the smoke

Likely causes

• CommonOil or coolant dripping onto a hot engine or exhaust surfaceBurns off and creates smoke and a corresponding smell without necessarily being a fire risk if caught early.
• CommonOverheating engine producing steam that looks like smokeOften white/gray and accompanied by a rising temperature gauge; technically steam from boiling coolant, not smoke.
• PossibleElectrical short or overheated wiringCan produce a distinct acrid smell and thin smoke, and carries a genuine fire risk if not addressed.
• PossibleA belt or component slipping and overheating from frictionFriction-generated smoke, often with a burning rubber smell.

What to do

1. Pull over safely and turn off the engine as soon as you notice smoke from under the hood; do not continue driving to 'see if it stops.'
2. Do not open the hood immediately if you suspect an active fire or see flames; call for help and keep a safe distance.
3. If it's clearly steam (white, thin, often with the temperature gauge high) rather than smoke, let the engine cool for at least 15–20 minutes before carefully checking the coolant system, and never open a hot radiator cap.
4. Once cool, open the hood carefully and look for the visible source: oily residue, coolant stains, or burnt/melted components.
5. Have the vehicle towed to a mechanic rather than driving it further if you can't clearly identify a simple, already-resolved cause.

When to call a pro

See a mechanic (via tow if needed) for any smoke from under the hood; this should always be treated as urgent rather than diagnosed by continuing to drive.

Safety