Tech Tip: Customer Complaining of Failing a Smog Test? – UnderhoodService

Tech Tip: Customer Complaining of Failing a Smog Test?

Do you have a customer who has a car that just can’t seem to pass a vehicle “smog test” to obtain a vehicle registration sticker? Depending on the state or county, vehicles need a smog check test every other year in order to re-register the car or truck with that state's Department of Motor Vehicles.

Do you have a customer who has a car that just can’t seem to pass a vehicle “smog test” to obtain a vehicle registration sticker? Depending on the state or county, vehicles need a smog check test every other year in order to re-register the car or truck with that state’s Department of Motor Vehicles.

The Automobile Club of Southern California recommends the following maintenance tips to ensure your customers’ vehicles are operating cleanly to pass a state-mandated smog check. However, the tips are intended to ensure that vehicles that should pass a smog check test do, and are not intended to “fool” the test equipment, according to an Auto Club spokesperson.

Most tips are especially important for teens, college students, retirees, telecommuters and others who are “short trip” drivers. If after following these tips the vehicle fails, then the vehicle needs a professional assessment of its emissions-related systems.

You can help your customers by offering the following 10 simple tips and advice:
1. Make sure the tires are in good condition and properly inflated.
2. Make sure the check engine light or any other dashboard warning lights are not on.
3. Make sure that the vehicle has no fluid leaks and no safety issues. Remember, the vehicle will be strapped down on a dynamometer and required to perform flawlessly under stressful conditions.
4. Don’t change the size of the tires from the original specifications. The dynamometer test equipment is calibrated to the “stock” tire size. Over- or under-sized tires will alter the speed calculations performed by the test equipment and may prevent the vehicle from going through the test since the machine won’t sense the correct speed for the vehicle’s tire size.
5. Make sure the vehicle has a clean air filter and fresh engine oil.
6. Make sure the vehicle’s gasoline cap fits the vehicle, isn’t damaged and is turned tightly in place. A vehicle without a gas cap is an automatic smog check test failure.
7. The week of the smog check test, take the vehicle out for an extended drive, preferably on the freeway and especially if they’re regularly a “short trip” driver. Drive approximately 30 minutes or longer at varying speeds on freeways, surface streets and up hills.
8. On the day of the test, have your customer fill the gas tank of your vehicle with the grade of fuel stated in the owner’s manual.
9. Make sure all fluids are topped off and that all non-essential items are removed from the trunk or the rear of the vehicle. The dynamometer weighs your vehicle before the test, and if the vehicle is heavier than it should be, the weight will make it harder to pass.
10. Drive at least 30 minutes before arriving at the smog check test facility to ensure the car or truck has reached full operating temperature.

Source: Automobile Club of Southern California.

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