Smog checks

Smog inspections are generally required during a vehicle's initial registration in California and once every two years thereafter. This inspection cycle continues for as long as the vehicle is registered in this state.

The Smog Check Program applies to 1976 and newer passenger vehicles and trucks: old vehicles, new vehicles, diesels, hybrids, RVs and duty trucks. Smog inspections are also required any time a vehicle is sold or bought in California.

Currently, smog inspections are required for all vehicles except diesel-powered vehicles 1997 model year and older or with a gross vehicle weight rating (GVWR) of more than 14,000 lbs, electric and natural-gas-powered vehicles over 14,000 lbs, motorcycles, trailers, or gasoline-powered vehicles 1975 and older.

The smog check exemption includes gasoline-powered vehicles four or fewer model years old whenever a vehicle is being bought or sold, unless the Air Resources Board determines that including the 5th and 6th model-year vehicles would prevent the state from meeting the federal Clean Air Act. This exemption does not apply to diesel-powered vehicles.

The six-year or four-year exemption does not apply to vehicles brought in from out of state that need initial registration in California. Both diesel and gasoline out-of-state vehicles require a smog check for initial California registration, and every two years thereafter.

Under the old smog laws, vehicles became exempt when they turned 30 years old (the 30-year rolling exemption). As of April 1, 2005, any motor vehicle manufactured before the 1976 model year is exempt, and all 1976 and newer vehicles are tested according to state emission law. This law repealed the 30-year rolling exemption.

• Two-wheel motorcycles
• Diesel cars and trucks, 1997 and older
• Diesel trucks over 14,500 GVW
• Title transfer between a spouse, domestic partner, sibling, child, parent, grandparent or grandchild
• A smog certification was submitted to the DMV within 90 days before the transfer date

All 1998 and newer diesel-powered vehicles under 14,500 GVW need a diesel smog check. There is no tailpipe emissions test and no dynamometer, so your vehicle is not driven on the rollers.

Instead, the diesel smog check is a visual inspection of your vehicle's emissions components, a system check of the On-Board Diagnostics (OBD II), a visual check for excessive black smoke, and an EVAP functional test. Diesels that fail are repaired at a diesel repair shop.

A hybrid electric vehicle uses an electric motor as part of its propulsion system, as well as an internal combustion engine. Since April 15, 2015, hybrids are smog tested every two years at registration renewal, at initial registration, and at any change of ownership (unless a smog inspection was done within 90 days of the sale date). Hybrids get the BAR-OIS test, with no tailpipe test.

Some models are also built as non-hybrids, for example the Tahoe, Camry, Civic and Escape. A few of the hybrids that need a smog check for California DMV registration:

• Chevy Hybrid Tahoe, all years
• Honda Insight, all years
• Honda Civic Hybrid, all years
• Lexus Hybrid RX, GS, LS, all years
• Toyota Prius, all years
• Toyota Hybrid Highlander, all years
• Toyota Hybrid Camry, all years