How to Pass the California Emissions Test

So you are just about ready to go get your California Emissions test done?  If you are nervous, don't the unlikely event that you don't pass the test, most of the time any problems can be fixed.


Keep in mind that it isn't just the emissions that your car will be graded on.  There is Emissions inspection, Visual inspection and Functional inspection.  


I will give just a few bullet points on what each test consists of, as well as some simple yet effective ways to help you get that A+ and remain on the honor roll.


What are some main things you can do to make sure you pass?  

  1. Maintain your car!  Performing routine tune ups, changing the spark plugs, the fuel filter, the air filter and regularly changing your oil will greatly improve your odds of passing.  
  2. No Warning Lights! Come on, if you have a check engine light on, go take care of your ride.  It will likely save you the embarrassment of failing a smog test too.
  3. Blow 'em up! Make sure your tires are inflated properly...and evenly.  Stop by a gas station and pay the 25 cents to fill up the tires.  They usually have a PSI indicator on them, and your PSI specification should be followed to the T.  They are usually found either in your gas cap, the drivers side door panel and of course in the owners manual.  Or, you could always try searching this site for the right inflation for your vehicle.
  4. Lube up! Make sure you are changing out your oil every 5,000 miles (this is not always necessary with luxury vehicles though..).  If you are at all worried you will not pass, if you don't do any of the other things on this list...change your oil a couple of days before the emissions test. 
  5. Joy Ride! Most people don't have a emissions test center/smog check shop around their you will probably already be driving.  However, if you are one of the unlucky folks that do (like me...I see 'Smog Check' outside of my urban apartment window every morning. Hi smog!) be sure to go for a little joy ride for about 30 minutes.  This helps to make sure all the fluids are at the right temperature when testing.  
  6. Let it drink! Additives.  Additives! Using some of those fuel additives found in the common gas station can make sure your engine is being cleaned of carbon deposits, intake and exhaust valves.  This will greatly increase your odds of passing the emissions test.


Here are some more detailed test descriptions as well that you will be tested on:

Emission Inspection:

During the emission part of the exam is conducted by the exhaust analyzer (aka the 'Smog Machine'..sounds grim).  This part of the inspection the smog machine is searching for any presence of Carbon Monoxides, Hydrocarbons (simply put, gasoline) and Nitrous Oxides(yes, the stuff you beg for at the dentist) in the exhaust.  This is the most typical of tests where, if your car is not performing well or isn't properly maintained, will fail.  

Visual Inspection Test:

Remember to keep in mind this part of the test. During the visual inspection test they will be looking to make sure certain compenents are installed and connected on the vehicle.

  1. Exhaust Gas Recirculation Valve (EGR)
  2. Catalytic Converter (CAT)
  3. Underhood Emission Label
  4. Positive Crankcase Ventiliation Valve (PCV)
  5. Oxygen Sensor (O2 Sensor)
  6. Air Injection System (AIR)
  7. Carburetor Pre-Heat Tube

You may or may not know what the heck these are based on your 'car nuttyness' rating in your profile.  Have your mechanic check these whenever you go in for check-ups.  


They will also be looking for any Vehicle Smoke.  If the inspector sees it, they will note it!  Any excessive smoke (white or black) will likely get you a failing grade.  If you do have visible signs right now, go back to my tips on getting oil changed and check-ups :-)  


Function Inspection Test:

This one actually gets pretty complex, but don't be worried - most cars pass this with flying colors.  

  1. Engine Ignition Timing - this basically means how quickly the vehicle fires up.  If your car seems to lag and struggle, get it to the shop 'cus you won't pass.
  2. Check Engine Light - Many people don't think of this when they go in for the emissions testing, because they don't know they will be checking the inside!  
  3. Gas Cap - during the inspection they will be checking to make sure the gas tap has the correct fit and is able to hold pressure.  The good thing is that most smog centers will sell you a gas cap that will fit should yours throw a failure.  
  4. Exhaust Gas Recirculation Valve - this is basically making sure that the valve responsible for taking small amounts of gas back into the combustion chamber is working properly.
  5. Low Fuel Pressure Evaporative Test - This test basically makes sure that you vehicle's fuel evaporative system isn't doing anything funky, I.E leaking deathly gas fumes into the atmosphere.  



Hope this helped with some questions.

Views: 1918


You need to be a FREE member of to add comments!

Join For Free



  • Add Videos
  • View All



Sustainable Member of the Eco Friendly U.S. Green Chamber of Commerce

© 2016   Created by Andrew.   Powered by

Badges  |  Report an Issue  |  Terms of Service