1. Clean or change your air filter at regularly specified intervals. Diesel powered vehicles require more air intake than petrol vehicles. A clogged air intake, such as a dirty air filter, will increase smoke.
2. Change the engine oil at least as often as recommended by the vehicle manufacturer. Dirty engine oil becomes very thick and will cause excessive engine and turbocharger wear leading to increased smoke emissions.
3. Maintain the engine’s fuel injection system, as recommended by the manufacturer. This includes:
   following recommended fuel filter change intervals
   regularly draining the water/fuel separator
   having injectors checked and cleaned to prevent plugging and replacing them when worn
   having the fuel injection pump maintained as needed.

An exhaust emission test is an easy way of checking whether your car is meeting recommended exhaust emission standards. A qualified mechanic can advise you how emissions from your vehicle can be reduced.

Petrol Vehicle Maintenance Tips
Excessive exhaust smoke can indicate engine problems. Here are some useful tips to keep your vehicle well maintained:

1. Change the engine oil at least as often as recommended by the vehicle manufacturer. Dirty engine oil becomes very thick and will cause excessive engine and turbocharger wear leading to increased smoke emissions.
2. Maintain the engine’s fuel system, as recommended by the manufacturer. This includes:
   following recommended fuel filter change intervals
   regularly draining the water/fuel separator
   having injectors or carburettor checked and cleaned to prevent plugging and replacing them when worn
   having the fuel injection pump maintained as needed.
3. Maintain the engine (including pistons and rings) to prevent the engine burning oil.

An exhaust emission test is an easy way of checking whether your car is meeting recommended exhaust emission standards. A qualified mechanic can advise you how emissions from your vehicle can be reduced.

1. Avoid prolonged wide-open-throttle accelerations from stops. Use moderate accelerations.
2. Avoid slowing the engine down in top gear (i.e. keep engine rmp up) by downshifting to a lower gear. Doing so will prevent your engine from labouring at low rpms.
3. Back off the accelerator under load conditions such as when climbing hills or towing a heavy load. The fuel delivered at near maximum throttle positions, under load conditions is simply making smoke, not power.

There is also a trend showing with the Year of Manufacture of these vehicles. (Most smokey vehicles were built in the 1980s.)