Go into any auto store and you'll see an entire shelf dedicated to products that guarantee to stop engine smoke. While a few will help temporarily, you can learn how to stop engine smoke by knowing what's causing it in the first place. While some types of smoke you needn't worry about, others are warning signals that serious internal damage could occur. Fortunately you can stop engine smoke relatively easily, no matter the cause.
Disconnect the negative (black) battery cable.
Pull out the engine-oil dipstick and smell it. If you have black smoke coming form your exhaust pipe and your oil smells of gas, your fuel mix is too rich or has too much gas and not enough air in it. Start your car and adjust your idle the fuel-mix screw on your carburettor until there's no black smoke when you press down on the accelerator. If your car is fuel-injected, put a fuel-injector cleaner additive in with your gas on your next fill up, which should clear up the problem.
Rub your fingers in the oil on the dipstick. If it is thick and creamy and you have white smoke coming from your exhaust, you have antifreeze contaminating your oil. Using a socket set, remove the bolts to the header, scrape off the old header gasket and replace the entire header gasket with the one included in your replacement engine gasket set. The most common cause of antifreeze contaminating your oil is the failure of a header gasket.
If you see blue smoke, oil is getting into your cylinders. There can be many causes for this, but most involve one of the many gaskets or o-rings in the valve and cylinder system failing or no longer fitting properly, which is common in older cars. Before you begin the job of replacing all the gaskets in the cylinder area, try draining all the oil from your engine and using a heavier-weight oil. That's enough to stop the leak in many old cars.
Start with simple fixes first like changing the weight of your oil if you see blue smoke before replacing all the gaskets in your engine. This will save you unnecessary repair work.
White smoke is an early indicator of potentially serious internal engine damage. Do not drive your car if you see white smoke and replace the head gasket immediately.