4 Common Reasons a Car Might Fail Inspection

Posted January 3, 2024

A failed emissions test can really put a brake on your plans. Vehicles fail emissions inspections for a number of reasons. The Daily Herald reports that about 7% of light-duty vehicles fail. Let’s look at a few reasons why cars fail and how you can fix the problem.

1. Clogged Air Filters

Sometimes emissions tests are failed for simple reasons. Clogged air filters for instance are a common cause for failure. The air filter in a vehicle is often overlooked, but this small component plays a critical role in the smooth function of your engine. If the filter is too dirty to catch debris, then the engine will soon be deprived of air. This has a negative impact on the engine’s performance. It also can’t filter out hydrocarbons and heavy metals. This will cause a failed emissions test. Luckily, this is an easy fix. You can grab an air filter for your particular vehicle at a local auto parts store and replace it before your emissions tests. Our mechanics suggest that filters should usually be changed between 15,000 and 30,000 miles.

2. Bad Catalytic Converters

When functioning properly, the catalytic converter is essential for passing the emissions. This device actually transforms the pollutants that come out of the engine. This is transformed into steam. Without a catalytic converter, the pollutants produced by your engine would move directly into the atmosphere. If the catalytic converter isn’t functioning properly, your vehicle will fail the emissions test. Although this can be annoying auto repairs, in the long run, this helps to protect the environment and keep the air in our communities clean.

3. Old or Dirty Engine Oil

Many people opt to get an oil change right before an emissions test because old or dirty engine oil can cause a failed test. According to MyCarNeedsA.com, you can keep up with your service intervals either in terms of mileage or time periods. To ensure that old engine oil doesn’t cause you to fail your emissions test, schedule your vehicle for service right before testing and get other auto repairs done.

4. Bad Air-to-Fuel Ratio

The air-to-fuel ratio in your vehicle is critical to ensure your vehicle creates safe, low-emission combustion. According to Motor Trend, the right ratio is 14.7 parts air to one part fuel. If this ratio is off, the fuel will not combust properly. This will create extra pollutants and a failed emissions test.

These are just a few reasons why your car might fail emissions testing. If you’re concerned about getting your car ready for testing, please contact Chase Automotive Repair Service today. We are here for your automotive needs.

Categories: Auto Repair Aurora

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