Your Tires Can Cause You To Fail A Smog Test

If you need to pass a smog test, don't just check under the hood. Sure, the condition of your engine and other systems is important if you want to pass the smog test. However, did you know that the condition of your tires is equally important? Before you unexpectedly fail your test, learn what tire red flags you should address.

Poorly Sized Tires

Make sure your tires are sized correctly, in that they aren't too large or too small. When a tire is too large or too small for a car to accommodate, this issue creates an imbalance that can cause a boost in the number of emissions that the car produces. 

If your vehicle emits a high level of emissions during the testing session, there is a real chance you could fail the smog exam. Unfortunately, even if the technician suspects the tire size is a contributing factor, by law, they are still required to give you a failing score. 

It's also worth mentioning that poorly sized tires are also unsafe as they can alter your ability to maneuver the vehicle safely and you might even see a reduction in your fuel economy. Check the manufacturer guidelines and choose a tire size that falls into the appropriate range. 

Underinflated Tires

A tire that is underinflated is an equally important issue when it comes to passing a smog test. To understand why you first need to understand the problem that underinflated tires create. When a tire is underinflated, it creates a bit of drag within the vehicle. 

For example, when you first press the gas, your car may not take off quite as quickly as it would if your tires were fully inflated. The drag puts a more considerable amount of pressure on the vehicle's engine and transmission. Whenever these two major systems have to work harder, your car will emit a higher amount of emissions. 

It's important to understand that when your vehicle is placed on the dynamometer for testing, your vehicle will operate just as it would if you were driving on the road. So, as a result, you will likely fail the test. If your tires happen to be overinflated, you won't likely fail the test, but it's not good for your tire's health. 

Don't let a tire issue keep you from successfully passing your smog test. Make the appropriate updates to your vehicle to ensure you don't run into any issues. Visit a site like for more information.