There might be a problem with your car if white smoke is coming out of its exhaust. Just how severe the problem is depends on the smoke type. The best-case scenario without serious implications is that the white smoke is because of condensation.
Regardless, drivers should understand what white smoke entails. By the process of elimination, you can narrow down what's causing the white smoke and make the job of inspecting your car easier for your mechanic when push comes to shove.
In particular, you should worry if there's a whole lot of white smoke billowing out of your pipe like clouds of cumulus, fog, or dry ice. The thicker the smoke the bigger the problem.
When White Smoke Is a Problem
- Condensation or Something More Sinister? Normally, white smoke means condensation has built up into your exhaust. If it's thin as vapor you don't have to worry about a thing. Thicker smoke can be something else entirely. For example, thick white smoke could be an indicator that there's something wrong with your engine coolant, which could indicate many expensive repair issues like a cracked engine block, blown head gasket, or damaged cylinder head. Don't ignore thick white smoke.
- Leaking Coolant: Leaking coolant can make your vehicle's gray smoke become white, thick, and foggy. This is most apparent when the white smoke makes its appearance while your vehicle is running instead of when you start it up. The white smoke happens because the leaking coolant has somehow gotten mixed up with your fuel. This leakage can also lead to your vehicle overheating. You should have your mechanic fix your radiator or hose or wherever the leak is coming from. Also, don't run your car that's low on coolant since it can damage the engine and other parts.
- Broken Fuel Pumping Injection: If you have a coolant leak, don't ignore it because it can lead to bigger damage on your car down the line. However, what if it isn't a coolant leak or accumulated condensation? What if your fuel injection pump is broken? This is common among diesel-powered vehicles. If there's lots of white smoke coming out when you start your engine and you have a diesel engine, then the timing to your fuel pumping injection might have been compromised. Have your mechanic check it out.
- Problems From Other Parts: Other parts of your vehicle can lead to your exhaust spewing out white smoke. To be more specific, it can root from damage with the fuel filter, head gasket, or cylinder head. An engine that's cracked and/or clogged can also lead to white smoke billowing from your tailpipe in excessive amounts. If the white smoke roots from those parts, then expect a rather expensive trip to the mechanic to have them fixed or replaced.