Sights, And Sounds, And Smells: Troubleshooting Clues From The Tailpipe

Blog

If you own a car, it's advisable to check its exhaust regularly for any changes that may signify mechanical trouble. The sights, smells, and sounds of the fumes from the tailpipe can tell you a lot about your car's condition. Here are some of the things you can learn this way:

Exhaust Fumes Color

Ideally, the exhaust fumes from your car's tailpipe should be nearly undetectable. Clearly visible exhaust fumes point to different issues depending on the color of the gases. Granted, some of the color-related diagnoses may not lead to critical issues (although you still need to fix them). For example, one of the signs of a clogged air filter is black smoke from the exhaust. Fortunately, in case the diagnosis is confirmed, replacing the air filter (which usually costs less than $100) solves the problem.

However, white smoke from the tailpipe, especially when the engine is running at normal temperatures, may point to a damaged or blown head gasket, which allows the coolant to enter the combustion chamber and get burned along with the fuel. Unfortunately, head gaskets replacements don't come cheap; expect to pay anything from $1,000 to $2,000 for the manufactured varieties, and more for brand new ones. In short, don't ignore colored fumes from your car's tailpipe because you may not know what it signifies; it may point to a critical problem that requires emergency repair.

Sounds from the Tailpipe

Apart from the color of the exhaust fumes, the noises from that part of the car can also tell you something about the engine's condition. Here are three common causes of exhaust noises:

• Loose heat shields – The shields prevent exhaust heat from causing damages or injuries to nearby objects or people (including the occupants of the car) respectively. If they are damaged and loose, they may start vibrating and cause discernible noises. This kind of noise sounds like a rattle or a buzz.
• Restriction in the exhaust system – Such a restriction may be caused by a damaged exhaust pipe. The restriction prevents smooth flow of the exhaust fumes and results in high-pitched hissing or whistling sounds. Restriction noise is usually accompanied by decreased fuel efficiency.
• Damaged or inefficient muffler – The muffler is meant to silence intrinsic exhaust sounds. It will not do this if you have replaced the original one with an ineffective aftermarket one, or if it is damaged.

Exhaust Fumes Smell

The exhaust system isn't meant to spew the spent gases exactly as they come from the engine; it is supposed to neutralize them so that the dangerous ones do not harm the environment. Therefore, if you smell something strange from your exhaust system, then something is wrong with your car.

For example, a rotten egg smell usually points to a damaged or plugged converter (which converts sulfur to harmless sulfur dioxide). If you can smell gas in the exhaust system, then there is a problem with the air-fuel ratio and the engine is getting more gas than it should; it is the excess ones you can smell at the exhaust.

Therefore, you don't have to be mechanically-minded to read the clues from your car's tailpipe. Just use your normal senses to know when your car has a problem. Don't forget to consult a professional mechanic for a correct diagnosis to help you fix the real problem.

Share

15 April 2016