Click Here For More Specific Information On:

By Lawrence Reaves

If your vehicle spews thick, black clouds of exhaust while you’re driving, it probably won’t pass a smog check. But, most drivers are not in that situation. Instead, their engines seem to run smoothly and nothing comes out of the tailpipe when they’re on the road. But, when they take their cars in for an emissions test, they’re surprised to discover they’ve failed.

As the health of our environment takes center stage, more jurisdictions are requiring motorists to undergo emissions testing. If your vehicle fails to pass, you’ll be required to have the problem – whatever it is – fixed.

Below, we’ll discuss which factors are reviewed during the testing process. I’ll also describe a few reasons your car may be on the verge of failing.

Are You A “Gross Polluter?”

YouTube Preview Image

The purpose of requiring drivers to have their automobiles smog tested is to identify “gross polluters.” These are vehicles that emit extremely high levels of hydrocarbons and carbon monoxide into the environment. Most testing facilities also look for carbon dioxide levels, but only for monitoring. That is, there is no cutoff point above which you need to have repairs done.

Individual states have been given the flexibility to design their emissions tests with varying cutoff points. So, California motorists may need to meet stricter requirements than people in Montana. Also, each state – and in many cases, different jurisdictions within a single state – set repair cost limits based on your vehicle’s age, make, and model. So, if you fail the smog check, there is a ceiling on the amount you’ll need to pay in repairs.

Possible Reasons There May Be A Problem

So, why might your car fail an emissions test? First, let’s talk about what causes excess hydrocarbons. If your automobile is above the cutoff point for hydrocarbons, it usually means fuel is getting into the exhaust without being burned in combustion. That might be caused by several things. For example, the exhaust valve might be malfunctioning which affects the compression of the air-fuel mixture. Or, there might be vacuum leaks, or the gasoline isn’t being delivered properly through your fuel injection system.

What about carbon monoxide readings that are too high? This, too, can be triggered by several things. For example, the gasoline within the air-fuel mixture may be too rich. Or, if you’re driving an older model with a carburetor, the choke may not be working properly. Another possible issue is a failing oxygen sensor.

If you receive your smog check readout and the readings for both hydrocarbons and carbon monoxide are too high, you may need to replace the catalytic converter.

In the end, your car’s results from an emissions test will usually be a mystery until you receive the readout. After all, you can’t see hydrocarbons or carbon monoxide coming from your tailpipe. Also, keep in mind that there are several things that can potentially cause an issue. If you fail the test, your best bet is to have an auto technician diagnose and fix the problem.

About the Author: For all your

used Honda Accord Parts


used Honda Civic parts

needs consider the leader in parts,


Permanent Link:

Sorry, comments for this entry are closed at this time.