Passing emission tests with a deleted diesel can be challenging, given the environmental regulations associated with it. However, you can pass emissions with a deleted diesel, or at least increase your chances of passing emissions. But the question is “Do states allow deleting your diesel?” Unfortunately, no state allows altering emissions in any way. Moreover, experts argue that “it never works” unless you know someone that knows someone.
How to Pass Emissions with a Deleted Diesel
If you made up your mind to follow this route, below are the ways to pass emissions with a deleted diesel:
1. Vehicle Tuning with OBD Scanner
On-board diagnostics (OBD) is a vehicle’s self-diagnostic and reporting capability, allowing you (the vehicle owner) or a repair technician access to the vehicle’s subsystems. When emission equipment is removed, the vehicle’s computer may register missing parts, triggering an error code.
In such situations, you can use an OBD II scanner. This diagnostic tool can read and erase error codes, enabling you to identify and troubleshoot any issues with your vehicle. They can also monitor the performance of your vehicle’s engine and other systems, providing valuable data to guide your tuning efforts.
Vehicle tuning involves adjusting a car to enhance its performance, speed, or responsiveness. After successfully tuning your vehicle with the OBD scanner, your vehicle’s computer will no longer display error codes, indicating that all systems are functioning as expected.
You usually would have to take your truck to a mechanic experienced in truck tuning. They will know how to maximize your vehicle’s performance while keeping it within acceptable emission standards.
2. Managing Smoke Density
Your vehicle’s smoke density can pass emissions with a deleted diesel or at least affect your chances. High smoke density can often indicate incomplete fuel combustion, which can lead to high emissions of particulates and other pollutants.
Managing smoke density involves ensuring that the vehicle’s smoke opacity does not exceed 20%. This can be achieved through vehicle tuning to improve combustion efficiency and reduce smoke density. If your vehicle emits smoke that is less than 20% dense, you are less likely to attract attention from traffic police and more likely to pass an emissions test.
3. Exchanging Emission Equipment During Tests
This is more of a workaround than a solution, and it relies heavily on the specifics of local emission testing procedures. In places where visual inspection of the emission equipment forms part of the test, you can swap out the old emission components for the duration of the test.
These components may include catalytic converters, Diesel Particulate Filters (DPFs), and Exhaust Gas Recirculation (EGR) systems, among others. After passing the test, you can remove these components again. While this can help you pass an emissions test, it is often viewed as deceptive or even illegal in most jurisdictions.
4. Routine Maintenance and Checks
Regular maintenance is a part of keeping any diesel vehicle in top working condition. And this is particularly true when trying to pass an emissions test with a deleted diesel. Regular oil changes, replacing old filters, checking the fuel system for leaks, ensuring the proper function of sensors, and other routine maintenance tasks can go a long way in ensuring that your vehicle stays within emission standards.
5. Use High-Quality Diesel
The type of fuel you use can determine your vehicle’s emissions. High-quality diesel fuels often contain fewer impurities and are designed to burn more cleanly, reducing the amount of particulate matter and other pollutants emitted from your truck’s exhaust.
Some high-quality diesel fuels also contain additives that can help clean and lubricate the fuel system. This will improve overall vehicle performance and potentially reduce emissions.
6. Emission-friendly Modifications
Some modifications can help improve a vehicle’s emission profile. These may include installing high-flow exhaust systems that can help reduce back pressure and improve engine efficiency, or performance air filters that can help enhance airflow and combustion efficiency. Also, consider upgrading the engine control unit (ECU) software to optimize the engine’s performance and reduce emissions in some way.
What Happens When You Delete a Diesel Engine?
Once a diesel delete procedure has been successfully carried out, issues related to soot accumulation are eradicated. Additionally, enhancements in performance may be observed, including a rise in both torque and horsepower, along with an upgrade in fuel efficiency. These beneficial transformations, however, can vary based on factors such as the tuner, the aftermarket software used, and the specifics of the engine hardware. Let’s tabulate other things that happen into advantages and disadvantages:
|Environmental Impact. Without emission control systems, diesel engine emits a higher amount of pollutants, contributing to air pollution.||Lower Maintenance Costs. Deleting emission control systems, such as DPF, can lead to lower maintenance costs.|
|Better Fuel Efficiency. The engine may operate more freely without the emission control systems, potentially leading to improved fuel economy.||Legal Issues. In many regions, deleting a diesel engine is illegal due to the increased emissions, and can result in significant fines.|
|Lower Maintenance Costs. The deletion of emission control systems, such as DPF, can lead to lower maintenance costs.||Voided Warranty. Vehicle manufacturers will typically void the warranty on vehicles that have been modified in this way.|
|Inspection Failures. Vehicles are often required to pass emissions tests, which can be more difficult or even impossible with a deleted diesel engine.|
Is it Better to Delete a Diesel?
|Benefits of Diesel Deletion||Drawbacks of Diesel Deletion|
|Increased Performance. Removal of emission control systems can lead to increased power and performance.||Environmental Impact. Deleting diesel significantly increases pollutants, contributing to air pollution and climate change.|
|Better Fuel Efficiency. The engine may operate more freely, potentially improving fuel economy.||Legal Considerations. In many areas, diesel engine deletion is illegal and can lead to fines or other penalties.|
|Lower Maintenance Costs. Deletion can lead to lower maintenance costs as emission control systems can be expensive to maintain or replace.||Voided Warranty. Manufacturers typically void the warranty on vehicles that have been modified with a diesel deletion.|
|Inspection Failures. Vehicles with deleted diesel engines may fail emissions tests, which are mandatory in many places.|
|Potential Future Sales. Selling a vehicle with a deleted diesel engine can be challenging, especially in regions with strict emissions regulations.|
What Happens if You Get Caught with a Deleted Truck?
Well, if it is illegal to pass emissions with a deleted diesel in your state, and you get caught, one or more of the following could happen to you:
In many places, driving a diesel truck with deleted emissions control systems is a violation of environmental protection laws. The penalties can be substantial, with fines sometimes reaching thousands of dollars.
In the most severe cases, especially for repeat offenders or in regions with particularly strict emissions laws, you could even face criminal charges for violating environmental protection regulations.
2. Mandatory Reinstatement of Emission Controls
In some jurisdictions, you may be required to reinstall the emissions control devices that were removed.
This process could be costly, especially if the original components were discarded during the deletion process.
If you live in a region that requires routine vehicle inspections, a deleted diesel truck is even more likely to fail an emissions test, which could lead to further penalties or restrictions.
3. Vehicle Impounding
In some extreme cases, authorities might impound your vehicle, and you could be required to pay additional fees to recover it. Meanwhile, we made an article explaining how to get a car out of impound without insurance.
4. Auto Insurance Complications
Your auto insurance company may also penalize you or even cancel your policy if they discover that you’ve modified your vehicle in a way that is illegal or increases risk.
Has Anyone Been Fined for DPF Delete?
Many people have been fined for DPF delete! First, PPEI and President Kory Willis plead guilty and agree to pay $3.1 Million in criminal fines and civil penalties for the manufacture and sale of illegal delete devices and tunes for diesel trucks – EPA (United States Environmental Protection Agency).
In another reported case, the DOJ (Department of Justice) hit the founder of Spartan Diesel Technologies with one year and one day behind bars for selling emission defeat devices. That’s on top of two million-dollar fines. In 2023, 11 men and 3 companies face federal charges for ‘deleting’ emissions controls from hundreds of semi trucks – reported by Michigan Live.
And lastly, but not least, a Nebraska diesel truck shop has been fined as part of a national crackdown on emissions controls, reported by Omaha.
Frequently Asked Questions
Will EGR delete pass emissions?
Of course, however, EGR deletes are illegal in the US, so removing your EGR system can lead to inspection issues and make your vehicle ineligible for street use.
Does deleting a diesel give better gas mileage?
Removing the DPF system can significantly boost fuel economy by up to 30%, enhancing overall truck performance. Diesel truck owners often seek increased power, horsepower, and torque for towing or carrying heavy loads.
What are the benefits of deleting diesel?
DPF delete offers three main advantages: increased engine power, improved fuel efficiency, and lower maintenance expenses. Deleting the DPF results in a more powerful and responsive engine, as reported by many owners.
Why do people delete their diesel engines?
A DPF delete alters the exhaust process to boost diesel engine performance, fuel efficiency, and torque. But it’s crucial to be aware of the potential risks and downsides involved.
Can you delete EGR and not DPF?
Do not remove the EGR Valve if your vehicle still has the DPF Filter. Doing so may block the DPF since the EGR Valve is necessary for DPF Regeneration.
What does fully deleted truck mean?
A diesel delete is the process of removing the DEF system, catalytic converter, and DPF and replacing the exhaust. The vehicle’s ECU needs to be reprogrammed with a tuner.
Read also: How to Avoid Emissions Testing in Colorado