How often does my vehicle have to be tested?
Smog Checks are required biennially (every other year) on vehicles more than six model-years old. Additionally, a Smog Test is required if you sell a vehicle that is more than four model-years old and when registering an out-of-state vehicle for the first time in California.
How can I help my vehicle pass a Smog Check?
Performing regular and proper maintenance according to your owner’s manual and not tampering with the emissions-control equipment will help improve your vehicle’s chances of passing a Smog Check. If the “Check Engine” light comes on, take your vehicle to a licensed repair station as soon as you can to have the problem diagnosed-do not wait for the vehicle’s next scheduled Smog Test. A blinking or flashing light indicates a malfunction that should be addressed immediately to avoid serious damage to the engine or emission-control systems. Check your owner’s manual for repairs that may be covered under your vehicle manufacturer’s emissions warranty.
What are the elements of a Smog Check?
Smog Checks are designed to measure the amount and type of pollutants your vehicle is emitting. A Smog Test may include any of the following tests:
- Visual inspection of emission control components and systems
- Functional inspection of the vehicle’s check engine light, ignition timing, exhaust gas recirculation system, fuel evaporative system, and gas cap
- Functional inspection of the vehicle’s On-Board Diagnostic (OBD) system
- Tailpipe emissions inspection
What vehicles require a Smog Check?
Gasoline-powered vehicles, hybrid vehicles, and alternative-fuel vehicles that are model year 1976 and newer require a Smog Check, with the following exceptions:
- Six model-years and newer do not need a biennial (every other year) inspection.
- Four model-years and newer do not need a change-of-ownership inspection.
To determine the first year a vehicle is subject to a biennial or change-of-ownership Smog Check, add six or four, respectively, to the model year of a vehicle. For example, a 2010 model-year vehicle will first be subject to a biennial Smog Test in 2016 (2010 + 6 = 2016) and a change-of-ownership Smog Test in 2014 (2010 + 4 = 2014).
Diesel-powered vehicles 1998 and newer with a gross vehicle weight rating of 14,000 pounds and less require a Smog Test.
Motorcycles and electric-powered vehicles are currently exempt from the Smog Check Program.
Is the Smog Check Program biased against older vehicles?
No. While California law requires the Smog Test Program to focus on high-polluting vehicles, the Smog Check Program also does not require older vehicles to meet the same emissions standards as newer vehicles. Smog Test emissions standards take into consideration the age, make and model of each vehicle, so that a vehicle is never held to a standard that applied when the vehicle was originally manufactured.
I have a vehicle that is six model-years old. My DMV registration renewal notice says it must have a Smog Check, but I thought it was exempt from the biennial Smog Test requirement.
A gas-powered vehicle is excused from Smog Check until it is seven model-years old. Department of Motor Vehicles (DMV) computers are designed to recognize the exemption and process your renewal accordingly. Contact DMV if you think there is an error. If you are unable to resolve the problem with DMV, a state Referee facility may be able to help. Call the Referee Call Center at (800) 622-7733 to schedule an appointment.
What is an Enhanced Area?
An Enhanced Area is an urban region designated by the U.S. Environmental Protection Agency as not being in attainment with federal health standards for ozone. Vehicles registered in an Enhanced Area are subject to a treadmill emissions test on a dynamometer and may require testing at a STAR-certified station.
Have California vehicle emissions standards changed?
Yes. BAR periodically adjusts some standards to increase their fairness. As a result, some standards become slightly more stringent than they were previously and some slightly more lenient. California’s emissions standards consider the model-year, vehicle make and model, and gross weight of the vehicle. Older cars have less stringent standards than newer ones. No older vehicle is ever held to the same standards as a newer, more technologically advanced vehicle. Allowances are made for normal wear and tear in a vehicle’s emissions control system as it ages. Standards are established through a regulatory process and are made available for public comment before they are adopted. The last adjustment occurred in 2010.