auto repair Fountain Valley auto repair Westminster auto repair Seal Beach

Smog Check and Emissions

Home > Automotive Repair Mechanics > Smog Check and Emissions

If you are reading this, you most likely did not pass your most recent smog check. Most vehicles require state mandated emissions testing every other year prior to registration with the DMV. If you failed the smog test, you will not be able to register your car until you pass. But, fear not, you have come to the right place. Automotive Excellence Inc. is in Huntington Beach and central to most of Orange County. We will diagnose your car and make the necessary repairs to your vehicle. We all love this beautiful planet of ours and making sure our cars run efficiently is one way to help keep our air clean. We have friendly and knowledgeable technicians standing by.

Call us today for an appointment: 714-841-1285.

Why didn't I pass my smog check?

The emission control system in modern cars consists of a catalytic converter (see catalytic converter page), a collection of sensors and actuators, and a computer to monitor and adjust everything. For example, the catalytic converter uses a catalyst and oxygen to burn off any unused fuel and certain other chemicals in the exhaust. An oxygen sensor in the exhaust stream makes sure there is enough oxygen available for the catalyst to work and adjusts things if necessary. Every new car, and most cars produced after 1980 have oxygen sensors. The sensor is part of the emissions control system and feeds data to the engine management computer. The goal of the sensor is to help the engine run as efficiently as possible and also to produce as few emissions as possible.

The oxygen sensor is positioned in the exhaust pipe and can detect rich and lean mixtures. The engine's computer looks at the voltage to determine if the mixture is rich or lean, and adjusts the amount of fuel entering the engine accordingly. When the oxygen sensor fails, the computer can no longer sense the air/fuel ratio, so it ends up guessing. Your car performs poorly and uses more fuel than it needs. After the engine exhaust gases pass the oxygen sensor they go through the catalytic converter, then the gases go through the muffler or mufflers, depending on the make of the automobile. Some vehicles use a pre-converter as well, to perform a similar function. The catalytic converter generally lasts the life of the automobile and rarely has a problem with being clogged or plugged during its lifetime as long as the engine and other emission components are properly maintained.

Oxygen Sensor - You won't pass a smog check without it.

smog check uses oxygen sensor

Catalytic converters help reduce emissions

emissions catalytic converter parts

EGR Valve - Might be the reason you failed a smog check

emissions egr valve

All of these components have to function properly in order to pass the state emissions test (smog test). If any one of these components is inoperative or missing or the engine is not tuned properly your car will fail the emissions test.

5 signs you may not pass the smog test