If you notice smoke coming from your engine bay or exhaust, it can signal anything from a minor oil leak to a serious engine problem. The colour of the smoke is often a key indicator of the underlying issue. An inspection will help identify the cause quickly and prevent further damage to your vehicle.

What does it mean if your car is smoking?

Smoke indicates that something is burning or leaking in the engine or exhaust system. Depending on whether the smoke is white, blue, grey, or black, the cause could range from coolant or oil leaks to fuelling or exhaust faults.

Common causes of smoke from the engine or exhaust

• White smoke: Coolant entering the combustion chamber (possible head gasket failure)
• Blue smoke: Oil burning due to worn piston rings, valve seals, or turbo issues
• Black smoke: Excess fuel being burned, often from faulty injectors, sensors, or air filters
• Grey smoke: Transmission fluid burning, PCV system fault, or oil leaks
• Oil or coolant dripping onto hot engine parts under the bonnet

Why do you need to fix this problem quickly?

Smoke usually indicates a leak or fault that can cause serious engine damage, higher emissions, or even a fire risk. Early diagnosis prevents more costly repairs and keeps your car safe and roadworthy.

How do you know when to get it checked?

You should book an inspection if:

• Smoke is visible from the exhaust or engine bay while driving
• The smoke changes colour, becomes thicker, or smells unusual
• Your car is overheating or losing coolant/oil
• The Check Engine Light is on

What happens during an assessment?

A mechanic will:

1. Identify the smoke colour and source
2. Inspect engine seals, gaskets, and fluid levels
3. Check the exhaust system, injectors, and sensors
4. Run diagnostic scans to identify engine fault codes
5. Pressure-test the cooling system if coolant leaks are suspected
6. Advise on necessary repairs to stop the smoke

How much does it cost to fix?

Costs vary widely depending on the cause. Minor oil leak repairs may cost $200–$400, while major issues like head gasket replacement can exceed $1,500+. Diagnostic testing usually starts from $120.

Is it unsafe to drive if your car is smoking?

Yes. Driving with smoke from the engine or exhaust can lead to breakdowns, engine damage, or even fire. The car should be inspected immediately before further use.