Emissions System Problem Honda: Common Signs and Fixes

The emissions system problem Honda results from a number of factors that owners often encounter over time when the vehicle is still in use. This problem indicates that the emissions control system is not working appropriately, causing the vehicle to pollute the air beyond the permissible limit. Consequently, a vehicle in this condition would likely fail an emission or smog check.

What Are the Signs of Emission Control System Problems in Honda


Continue reading as this article provides comprehensive and valuable information on the emission system problems of the Honda Pilot, the likely causes of this issue, and the steps to fix the emission system errors.

What Are the Signs of Emission Control System Problems in Honda?

The signs of emission control system problems in Honda cars include warning lights or error codes on the dashboard, rapid fuel consumption, a sudden decrease in the level of performance, noises coming from the engine, and a strong smell of fuel around your vehicle.

Over the years, the emissions system problem has been strangely linked to Honda Pilot vehicles, particularly the 2016, 2017 and 2018 models. Don’t get us wrong! Honda Pilot is a great vehicle, but like any other automobile, it also has its fair share of issues. A major problem of the Honda Pilot is the emission system problem.

Before delving right into the emission system problem, you need to understand how the emission control system works in vehicles. Modern vehicles comprise sophisticated emissions systems designed to burn off and reduce the emission of toxic exhaust gases. However, it would be best not to depend on this technology because the system can malfunction anytime while driving. 

For this reason, knowing the common signs of emission control system problems will help you identify this issue early enough. As a result, you can avoid incurring expensive repair charges for your Honda Pilot. 

Warning Lights or Error Code on Dash

Most modern vehicles have very advanced sensors that alert drivers when there’s a potential emission issue. To a large extent, the check engine light service provides the fastest warning indication of an emissions system problem. The problem could result from issues with the exhaust leak, failing catalytic converter, loss of pressure, or a malfunctioning oxygen sensor

Thus, the check engine light comes on the dash to alert the driver of the pending issue. It would be best if you didn’t take any chances when the check engine light or other warning lights come on in your vehicle while driving. 

– Rapid Fuel Consumption

Another common sign of an emission system problem is poor fuel economy, designating that your vehicle is consuming more fuel than normal. In most cases, automobile fuel evaporates rapidly, even when the car is not running, due to its high volatility. 

Rapid Fuel Consumption

The emission control system is designed to check the loss of those gases from the fuel pump. So if the emission system is not functioning correctly, you could find that your Honda Pilot is burning more gas than usual.

– Depleted Performance

As your vehicle’s engine burns fuel, the emission control system works alongside the engine’s intake system to properly burn off dangerous gases before expelling the fumes through the tail pipe. Meanwhile, if the emission system is faulty, the engine won’t perform optimally as it should. Consequently, this results in several performance issues with your Honda Pilot.

Like every other mechanical part of an automobile subjected to constant use, the emission control system also develops problems and requires repairs. The emissions problem indicates that the vehicle’s emission control system is faulty. 

Unfortunately, the Honda Pilot emission control system problem results in the release of toxins causing various health issues. To name a few health problems, the released toxins may cause cancer, carbon monoxide poisoning, headaches, nausea and asthma.

As such, emission problems or exhaust system failure remains environmentally unfriendly. Aside from discharging potentially harmful fumes into the environment, the Honda emissions system problem also causes several performance issues in the engine. This potentially leads to costly internal damages.

– Engine Noises and Smell of Fuel Around Your Vehicle

Typically, the scent of automobile fuel is impossible and hard to miss. If you perceive an oddly intense smell of fuel while your vehicle is running or idling, it could indicate emission problems or exhaust system issues. Aside from this, when you notice unusual engine knocks or vibrations while operating your vehicle, keep in mind that a defective emission system can cause this. 

The emissions control system comprises a range of sensors, exhaust components and computerized engine control parts. These components work hand in hand to control the emissions and pollutants discharged from the exhaust pipe while driving. Three main components release gases: the fuel tank and carburetor, the internal combustion engine, and the crankcase. 

Take note that these components are also necessary to keep vehicles running. Thus, the system’s primary function is to lessen the release of noxious or harmful gases from these sources. The toxic gases include carbon monoxide (CO), oxides of nitrogen (NOx), and unburned hydrocarbons (HC).

Many local agencies in the United States such as the Environmental Protection Agency at the federal level control the overall permissible emission limit of vehicles. While the emission control system aims to prevent environmental pollution, it also helps protect public health.

What Are the Common Causes of Emissions System Problems Honda?

The common causes of emissions system problems in Honda vehicles include a defective oxygen sensor, a damaged fuel injector, a defective catalytic converter, an exhaust system leak, and a congested or dirty air filter. Several things can lead to the emissions system failure in a Honda Pilot.

Most of these issues get resolved with a quick repair or adjustment. However, if the problem is not fixed or allowed to persist for a long time, it could result in more severe issues like engine damage or transmission failure. 

Check the causes of emission system problems below:

– Defective Oxygen Sensor

The oxygen sensor is a crucial part of the emission control system that monitors the oxygen level in the exhaust gas discharged from the engine. Once it senses an increase in emissions above the usual, it activates the warning light.

Therefore, a faulty oxygen sensor will affect the engine’s timing and combustion intervals, which impacts the adjustment of the air-fuel mixture. Thus, this leads to an increase in the emission of harmful fumes.

– Damaged Fuel Injector

Fuel injectors regulate the volume of fuel that gets delivered to the combustion chamber, ensuring the proper amount is injected when needed. The fuel pump pushes petrol or diesel through the fuel lines to the injectors to transport the fuel into the engine cylinders.

Damaged-Fuel-Injector (1)

As such, faulty fuel injectors on a Honda Pilot will cause a decrease in the amount of fuel delivered to the engine. Thus, this causes engine overheating and can lead to an increase in emissions.

– Defective Catalytic Converter

The catalytic converter is another vital component of the emission control system. It helps filter and converts the exhaust fumes’ harmful byproducts into less harmful ones. As such, a faulty catalytic converter will cause an increase in emissions. It also leads to declining automobile efficiency and slow acceleration or stalling.

– Exhaust System Leak

Exhaust system leaks occur when the exhaust fumes produced from the engine’s combustion chamber leak out from the system to the vehicle’s cabin. This is especially dangerous for the passengers in the car. Also, this makes the engine operate less efficiently.

– Congested or Dirty Air Filter

A dirty or congested air filter often limits the flow of air to the engine. This, in turn, causes the engine to run less efficiently and increases the release of harmful gases.

How Do You Fix Emission Control System Errors on a Honda?

To fix emission control system errors on a Honda car, you should first inspect and clean the air filter. Next, you should examine the positive crankcase ventilation and check the evaporative emissions control system. Inspect the exhaust gas recirculation system and the air injection system as well.

Some auto technicians conclude that your Honda Pilot needs specific replacements when considering emission control system errors. However, this may not be the case every time, as replacement may not completely fix the issue. 

Besides, further investigation often shows that some errors occur due to a malfunction of the emission system component that triggers these errors. Check the tips to fix the emission control system errors below.

– Inspect and Clean the Air Filter on the Air Cleaner System

The Air Cleaner System is responsible for pulling air from outside the vehicle and filtering it before delivering it to the engine. In the meantime, a clogged or dirty air filter causes various emission system errors, so examine and clean the air filter when an emission system error occurs. 

– Examine the Positive Crankcase Ventilation

The Positive Crankcase Ventilation, or PVC for short, is responsible for directing unburned gases from the engine unit back into the combustion chamber for proper conversion. If this process gets impaired, those unburned gases will leak through the dipstick tube to the vehicle’s hood. To confirm if the PCV is the cause of your emission transmission error, do the following:

  • First, remove the gas cap and start the engine. 
  • If you see fumes coming out from under the hood, then this indicates that your PVC is not functioning properly.

– Check the Evaporative Emissions Control System

The Evaporative Emission Control System recirculates the fuel tank’s fumes through the carbon canister. This system is usually incorporated into vehicles that utilize a closed fuel system, where fumes are vented directly into the atmosphere.

If your Honda Pilot uses this system and it’s not working correctly, it can trigger the check engine light to come on or display the emission control system error.

– Inspect the Exhaust Gas Recirculation System

The Exhaust Gas Recirculation (EGR) system is one that recirculates exhaust gases into the engine for re-burning. A problem with the EGR system can cause Honda Pilot to release more pollutants than usual.

To check the EGR system, follow the steps below:

  1. Start the engine and leave it idle for five to ten minutes.
  2. Afterwards, turn on the A/C and place your hand at the end of the tailpipe.
  3. If you feel an intense suction coming from the tailpipe, there’s an issue with the EGR system. Make sure to have this problem fixed as soon as possible before you continue driving.

– Examine the Air Injection System

This system works by injecting a little air into the exhaust line to help perfect the combustion process and limit the release of harmful gases. Thus, if this system is not working correctly, it can cause the engine control unit to display specific check engine light codes on the dash.

Check the steps to examine the air injection system below:

  1. Find the air injection pump outlet.
  2. Examine the pump for leaks, particularly in the hoses or fittings.
  3. Ensure the pump is receiving enough power.
  4. Examine the check valve and solenoid valves.
  5. Check for blockages in the air injection line or passages.

– Refrain From Driving the Vehicle

Whether or not it is safe to drive a car with an emission system problem depends on how long the issue has popped up. For instance, if you’re driving and you notice that the check engine light comes on your dashboard, it is safe to drive a few miles before you inspect the vehicle or seek assistance from a professional. But then, you must pay closer attention to confirm if the vehicle is not responding differently than usual.

Refrain From Driving the Vehicle

On the flip side, take note that it is unsafe to drive with an emission system problem that has surfaced for a few days. This is because persistent driving with the issue might cause further serious or irreparable damages to the catalytic converter, fuel pump, sensor and other vital parts.

What Are the Top Ways to Avoid Emissions System Problem Honda?

The top ways to avoid emissions system problems in your Honda vehicle include going for regular automobile maintenance, getting acquainted with the signs of potential emission system problems, and purchasing high-quality fuel. Here are a few tips to help you avoid having an emission control system problem:

– Regular Vehicle Maintenance

This involves frequently examining and changing your oil, inspecting hoses, fittings, and exhaust lines for leaks, cleaning the air filter, and performing other routine maintenance tasks. Put together; these regular maintenance activities will help prevent the occurrence of emission system problems.

Regular Vehicle Maintenance

– Get Acquainted With the Signs of Potential Emission System Problems

The sooner you notice the signs of emission system problems, the better. That way, you can quickly have your vehicle examined by a professional auto technician before any severe damage occurs.

– Purchase High-quality Fuel

Using high-quality fuel for your vehicles will help prevent the contamination of your emission control system. This further provides a hitch-free emission system operation and ensures longevity of your car parts.

Frequently Asked Question

1. How Much Does Fixing the Honda Emissions System Problem Cost?

Fixing the Honda emissions control system problem varies depending on the root issue, but replacing the fuel injectors on a Honda Pilot costs around $300, while the labor charges depend on the auto-technician fixing the vehicle. Regardless, most mechanics charge anywhere from $300 to $400 for labor.


We discussed the emissions system problem on a Honda in this article. Here are some of the crucial points we mentioned:

  • The emission problem indicates an issue with the vehicle’s emission control system that can lead to several damages.
  • The signs of emissions system problem on a Honda Pilot include warning light and error code on the dash, rapid fuel consumption, depleted performance, engine noises, and intense smell of fuel around the vehicle.
  • Several factors can cause the emission system problem, ranging from simple issues like clogged air filters to more serious problems like a faulty oxygen sensor, defective catalytic converter, exhaust system leak, and damaged fuel injector.
  • You can prevent emission system problems through regular maintenance, learning the signs of emissions issues, and using high-quality fuel.

If your Honda is experiencing an emission system problem, it’s essential to have your vehicle examined by an expert mechanic so that they can diagnose and resolve the issue. Otherwise, you risk damaging your engine or causing other severe problems while you head down the road.

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