Smog check resources
Featured guides
Gross Polluter: What It Means and How to Fix It
A gross polluter is a car whose initial smog test came in at roughly twice the legal limit. The label sticks to the vehicle record. Here is what it costs you.
Buying a Used Car? Check Its Smog History First
California keeps a public record of every smog inspection a vehicle has taken. Before you buy a used car, spend two minutes reading it. Here is what to look for.
The Check Engine Light and Your Smog Check
An illuminated check engine light fails a California smog check automatically, no matter how clean the exhaust is. Here is why, and what to do about it.
Why Did My Car Fail? The 7 Most Common Smog Check Failures
From a lit check engine light to a $2,000 catalytic converter, here are the seven failures that send California cars home with a red slip, and what each costs.
Smog Check for Registration Renewal: When It's Due and When It Isn't
California smog checks are due every other year at renewal, but the notice is the real authority. Here's how the cycle lands and when testing early wastes money.