How to Pass Smog Test Illegally

It can be frustrating living in a state that requires emissions testing, especially the notorious California with strict emissions regulations. Consequently, any car modifications beyond a basic axle-back exhaust system could lead to a failed biennial smog test. Additions such as downpipes, mid-pipes, or headers are almost certain to lead to a failed smog test. Even something as simple as an aftermarket intake could result in failing the visual inspection. All these tempt you to want to pass smog test illegally. So, for people with heavily modified cars that are far from being smog-compliant, how do you handle your smog checks?

How to Pass Smog Test Illegally

Numerous urban legends and unverified claims circulate about how to unlawfully pass smog checks. Some suggest rolling down the car windows during the test to expel exhaust gases, while others propose sealing your vehicle’s emission ports using chewing gum or duct tape. But are these true? Let’s look at the ways vehicle owners pass smog test illegally.

1. Unauthorized Smog Checks

You are in a bit of a bind and not sure what to do next. Dismantling your whole car or buying a similar Integra to switch VINs seems like too much hassle. According to popular opinion, an unauthorized or under the table smog check costs upwards of $250 these days.

One option could be to take it to a local garage and be honest about your situation — your car isn’t going to pass, and you need a workaround. It might require paying a bit more, but it is a possible solution. Some people have been using this approach for years now, mainly due to OBD2 to OBD1 conversion that affects the smog check.

However, finding a local garage that does smog checks illegally can be tough, especially if your car is far from passing a smog test.

One word of caution though, you have to be careful about using a state referee for your smog checks. If the referee does not pass your car and you take it to a less reputable place for the smog check, you might face an audit. You only want to go to a BAR smog referee if your vehicle is fully compliant, with all the emission equipment and controls in working condition.

2. Use Pure Ethanol

Some people have had success with using pure ethanol (100%, not the 70% version) in large amounts to lower HC and CO levels to compensate for a rich condition. Methanol also works as it encourages cooler combustion but it is illegal. Regular use of these additives can damage rubber parts within the engine.

Do note that applying additives to clean your engine is not illegal, but using them to manipulate the smog test is.

Moreover, an oil change right before the smog test and installing new plugs could help to pass a smog check.

Your personal plan should include finding a clean, stock LS motor (if your car is originally an LS) once the smog check is done. You can then swap this engine in whenever it is time for a smog test.

Swapping your engine might not be the easiest way to spend a weekend, but it could save you trouble in the long run. Also, if you ever get caught and have to face a referee, you can always switch back to the stock engine. And if you decide to sell the car, you can sell it with a stock engine. So, a backup engine might be a smart investment after all.

3. Go for Explicitly CARB-approved Parts

Some drivers resort to hot smog tests, which can be costly (over $300), and become less appealing when added to the yearly registration fees. Therefore, it might be best to go for explicitly CARB-approved parts, despite them being typically more expensive and less common.

This approach saves several hundred dollars over a few years by avoiding hot smog tests, but it also supports the industry in developing products that allow Californian car enthusiasts to enjoy the art of modifying their vehicles.

There are CARB-compliant options available for most vehicle models, and non-emission-related components can be modified freely. If you are keen on specific modifications, it makes sense to choose the right vehicle model (or go for pre-1975 vehicles) that have several Executive Orders (EOs) in place.

For a car model like NC Miata, CARB-approved options like headers, intake, midpipes, mufflers, and even superchargers and turbochargers are available. Certain components may raise questions about modification, which can quickly turn into a gray area – these parts might keep your vehicle emissions compliant while offering added performance.

Modifying vehicles for the sake of enhancing performance can be debated though, but 99% of the joy in modification comes from the hands-on process of swapping parts. It’s about the journey, not necessarily the result. Is there a substantial difference between a CARB-compliant part that gives an extra 5 horsepower and a non-CARB part that adds 7 horsepower? Probably not. Any marginal performance gains become nearly irrelevant on a race track – it’s essentially a non-factor.

You may be able to gain access to a variety of affordable options and year-round enjoyment at venues like Chuckwalla, Thunderhill, Laguna Seca, Fontana Autoclub Speedway, Willow Springs, Buttonwillow, Thermal, and Infineon Raceway. So, find the positive side of living in a restricted state, get on track, and make the most of your property tax dollars.

The straightforward, albeit pricier approach, is to invest in smog-legal modifications. Opt for CARB-exempt parts and steer clear of elements like catless downpipes, ensuring a hassle-free smog check when the time comes.

4. Find a Station that will Pass Your Car for an Extra Fee

You could locate a shop that will pass your vehicle for an extra fee. Given the potentially high cost for them if they get caught, it may not be an easy task to find such a shop, and they may not be around by the time your next smog check is due.

In 2020, about 9 smog check stations were caught using “clean gassing” to issue fraudulent certificates in California – Department of Consumer Affairs.

5. Become a Resident of a Smog Free County

If you happen to reside in a California county that doesn’t require a smog check, then you don’t need emissions testing at all. But if you don’t reside in one, it might require a bit of effort to establish an address in such a county. The counties in California that are exempt from smog checks include El Dorado, Riverside, Placer, San Diego, San Bernardino, and Sonoma.

6. Use CRC Guaranteed to Pass Emissions Test Formula

CRC’s Guaranteed to Pass Emissions Test Formula is designed to lower your vehicle’s emissions while enhancing power, performance, and fuel economy in one application. This product uses a potent detergent to soften and eliminate fuel system sludge, effectively clearing out deposits and residues.

The advanced detergent blend is suitable for all vehicles, SUVs, trucks, and hybrids that run on gasoline or ethanol mixtures. It is considered safe for all types of gasoline engines, whether they use Direct Injection (GDI) or Port Injection (PI), irrespective of whether they have turbochargers or superchargers (according to popular opinion). CRC’s Guaranteed to Pass Emissions Test Formula typically comes in a 12 fl oz bottle.

Ways Smog Check Stations Illegally Pass Smog Test

Dishonest smog check stations have been known to use these common methods to pass smog checks illegally:

1. Clean Plugging

This method is used to pass smog test illegally by obtaining engine computer data (OBD II Data) from a vehicle that has passed the test and using it to replace the data of the vehicle actually being tested.

2. Clean Piping

This is the unauthorized practice of substituting the emissions sample (tailpipe exhaust) from a passing vehicle for the vehicle currently being inspected.

3. Tach Simulator

A tach simulator works by using an ignition pulse simulator to deceive the smog machine into thinking that a vehicle is operating at the suitable and passing RPM.

4. General Test Manipulation

This involves incorrect testing of a vehicle, such as testing when it is overheated or underheated, conducting the test at above or below the required dyno speeds, and varying drive speeds during the smog test.

Fines and Penalties for Illegal Smog Check

For the consumer

If you attempt to pass a smog check illegally, you may face a civil penalty of no less than $150 and no more than $1,000, depending on your state.

For the station owner

Station owners can be fined anywhere between $5,000 and $250,000 depending on the amount of investigation time the Bureau of Automotive Repairs needs to press charges.

Penalties are typically paired with the revocation of the smog station’s and smog technician’s licenses. For less serious offenses, usually due to negligence or improper training, the initial fine is $1,000. Subsequent offenses could see the fines double to $2,000 and triple to $3,000, with mandatory attendance at training classes in all instances.

What is the best Way to Pass a Smog Check?

Perhaps, you might want to think again about cheating on a smog check and instead do the right thing.

1. Stay Ahead of the Curve

As soon as you receive a notice for your registration renewal, indicating a smog check requirement, mark the date in your calendar and start preparing.

Note that your new registration will only be issued once the smog test is successful. Smog check requirements differ across states, with most requiring emissions tests biennially or before a car sale. Costs, preparations, and testing methods can vary. For instance, certain stations may use a dynamometer test, particularly for older vehicles (which simulate driving conditions by enabling the wheels to spin).

Therefore, always inspect your notice to identify if you need to bring your vehicle to a specific type of station.

2. Increase the Warmness of Your Engine

Your car engine uses fuel combustion to ensure optimal efficiency (i.e., it’s operating as cleanly as possible). The warmer your car’s engine, the fewer hydrocarbons it emits through the tailpipe.

For even better results, test your car on a relatively cool day, while keeping your engine as hot as possible. Cars that take in cooler air function more efficiently, which is evident in smog monitoring equipment.

3. Use a Fuel Additive

You can have a fuel additive poured into your gas tank during refueling to clean carbon deposits from your engine’s exhaust and intake pathways. It ensures smooth air and fuel flow through these passages, reduces emissions rate, and improves your engine’s efficiency and combustion.

4. Ensure your tires are inflated towards the high end of the range

During the smog test, the technician might need to drive your vehicle on a ‘dynamometer’. Ensure your tires are appropriately inflated before this test.

If your tire manufacturer specifies a safe inflation range for your tires (say, anywhere between 35 and 45 PSI), inflate them to the top end of that range.

This higher tire pressure allows your engine to rotate the wheels with less effort, meaning your car will run slightly cleaner at 25 MPH with tires inflated to 45 PSI compared to tires inflated to 35 PSI.

5. Change your oil before the smog test

Your car’s positive crank ventilation (PCV) system is designed to enable your engine to vent the fumes from the oil compartments, which are burnt during the combustion process. If your engine oil is contaminated due to infrequent oil changes, it could lead to higher emissions and a failed smog test.

If the check engine light is on, get it turned off. An illuminated check engine light or malfunction indicator lamp (MIL) will result in an immediate smog test failure. If you bring your car to a professional repair technician, they should be able to diagnose why the check engine light/MIL is on and provide an estimate to fix the issue, usually at no cost.

6. Address Check-Engine Light Issues

An illuminated check engine light indicates an issue that needs immediate attention. Triggers for the check-engine light can range from cheap fixes, such as a loose or damaged gas cap, to costlier, serious repairs. So, make sure to identify and resolve the cause of the check engine light illumination before the smog test.

However, even after the check engine light has been cleared post-repairs, you want to drive your car until its computer confirms the proper functioning of the systems.

7. Run a Pretest on Your Car

AutoZone, for example, offers a free diagnostic analysis that you can use to pretest your car’s readiness for the smog check. These diagnostic tests are not exclusively for smog checks but they can alert you to any unresolved issues. This is especially beneficial if your car has recently undergone repairs or if you are concerned about an older car failing the test.

Takehome Tips

Final Thoughts

There’s no guaranteed method to cheat and pass smog test illegally. Nevertheless, you can adopt the mentioned tips to improve your chances. Just keep your car in good condition and ensure proper maintenance. Understand that smog tests help in controlling pollution, even though they may seem inconvenient. If your car fails the test, consider repairs at a service center and try the mentioned methods to enhance your chances of passing.

Read also: How to Judge Distance When Changing Lanes