Smog rules, calmly answered
Ask the Guru.
Do you need a smog check? Tell the Guru your car, fuel and situation. The answer comes from BAR and DMV rules. Then book a station near you.
Every car has its rule.
Gas and hybrid cars from 1976 on, diesels from 1998 on. Electric cars, never. Tell me yours.
Read it at BARWhat people bring up the mountain
Five questions,
one calm answer.
Nobody climbs for fun. They climb because a notice came, a buyer is waiting, or a light came on. Find yours.
"My renewal notice asks for smog."
A smog check is required every other year to renew. Newer gas cars pay a fee instead for their first eight model years. BAR
Book a check"I'm selling my car."
The seller gives the new owner a valid smog certification. If the car is four model years or newer, the buyer pays an $8 transfer fee instead.
Book a check"I'm buying from a private seller."
BAR says the car must have passed a smog check within the last 90 days. Ask the seller for it before you pay.
Book a check"I just moved to California."
A smog check is required to register a vehicle here for the first time. It also confirms aftermarket parts meet California rules.
Book a check"My car failed."
Read the inspection report, repair, retest. BAR's Consumer Assistance Program may help eligible owners with repairs. CAP
Find testing"The check engine light is on."
BAR advises a repair as soon as possible. A blinking light should be dealt with right away. Clear it before the test.
Find a shopWhat the test sees
The inspector
looks within.
- 1
2000 and newer: the computer
The station connects to the on-board diagnostic system, which records how the car runs in everyday driving. BAR
- 2
1999 and older: the tailpipe
Older cars get a tailpipe emissions test on BAR's emissions inspection system.
- 3
The warning light
The malfunction indicator light, your check engine light, is checked with the key on and the engine running.
- 4
The parts themselves
A visual inspection looks at emission control parts, labels, fuel leaks and visible smoke. Smog Check Manual
The rule of eight and four
Count like
the Guru.
For gas, hybrid and alternative fuel cars, BAR gives two simple sums. Add eight to the model year for the first renewal check. Add four for the first check when you sell.
BAR's own example: a 2020 car first needs a renewal check in 2028, and a check to sell from 2024.
From the BAR Smog Check brochure and BAR's Smog Check page. Diesels have no model year exception. Your DMV notice is the final word.
Ways up the mountain
Book the
right test.
Smog check
For your renewal, a sale, or a first California registration. Stations near you quote it.
Get quotes →Emissions testing
Failed once, or want to know before the real test? Find a shop that tests emissions.
Get quotes →Check engine light
Find out why the light is on and get it fixed before the inspection.
Get quotes →Engine diagnostic
When the inspection report points at a problem, a diagnostic finds what to repair.
Get quotes →The lineage of clean air
How the valley
learned to breathe.
Every rule the Guru knows came from somewhere. It starts in a Los Angeles haze.
The first smog
The first recognized smog episodes hit Los Angeles in summer. Visibility dropped to about three blocks.
The cause is found
Dr. Arie Haagen-Smit of Caltech shows that hydrocarbons from gasoline and nitrogen oxides from engines cause smog.
A first remedy
California mandates positive crankcase ventilation, the nation's first auto emissions control.
The first tailpipe limits
California adopts the nation's first tailpipe standards for carbon monoxide and hydrocarbons.
CARB is born
On August 30, the Mulford-Carrell Act creates the California Air Resources Board.
Smog Check begins
The California Smog Check Program takes effect.
Cars learn to self check
CARB adopts on-board diagnostics rules, effective for 1994 and newer models.
The test reads the computer
From September 1, 2000 and newer cars are inspected with the OBD based test.
Hybrids join
Hybrid vehicles become subject to smog check requirements in April.
Ask, then book
Ask the Guru, compare stations near you, and pick a time on Lokuli.
Sources: CARB history, CARB emission control timeline, CARB on the OBD test, Wikipedia's Smog Check Program article.
The teachings
Scrolls for
common doubts.
Do I need a smog check every year?
No. For renewal, California requires a smog check every other year. Your DMV renewal notice says "Smog Certification Required" when it's your year.
Which cars never need one?
Electric vehicles, motorcycles, gas vehicles from 1975 and older, and diesel vehicles from 1997 and older or with a gross vehicle weight rating over 14,000 pounds.
My gas car is almost new. Do I need one?
For renewal, gas, hybrid and alternative fuel cars eight model years and newer pay a smog abatement fee instead, listed at $20 on the DMV fee page. Add eight to the model year to find the first check.
Do diesels follow the same rule?
No. BAR says there are no model year exceptions for diesel vehicles. Diesels from 1998 and newer need checks, unless they weigh more than 14,000 pounds gross vehicle weight rating.
Who gets the smog check when a car is sold?
The seller. They give the new owner a valid smog certification. Cars four model years and newer skip it, and the new owner pays an $8 smog transfer fee.
A family member gave me a car. Now what?
BAR says a transfer between immediate family members doesn't require a smog check. If a family member bought it for you, a check is usually required.
How long is a passing result good for?
90 days. The station sends the certificate to the DMV electronically.
I'm moving here with a nearly new car. Anything special?
A smog check is required for the first California registration. Also, the DMV may not register a car under two years old with under 7,500 miles unless it was built to California emission standards.
What is a STAR station?
A station certified under BAR's STAR program, which holds stations to higher inspection standards. Your renewal notice says if you must use one.
How much does a smog check cost?
Each station sets its own price. Stations quote you through Lokuli, so you can compare before you go.
Where the Guru reads
The source
texts.
No guesses. Every answer on this page comes from these state pages.
How it works
Ask. Book.
Breathe.
- AskTell the Guru your carYear, make, model, fuel and ZIP. You'll know if a check is likely due.
- BookPick a station and timeCompare smog stations near you and request a slot on Lokuli.
- BreathePass and move onThe station sends your result to the DMV electronically. Finish your renewal or sale.
Near you
Stations in
the valley.
Run a smog station?
Let seekers find you.
Smog Guru sends drivers to stations on Lokuli. Claim a booking page free, take requests online, and pay no commission on any plan.