Back to all

Why did my vehicle fail its emissions test?

November 17, 2024

We all want to breathe clean air and keep our planet green.  One of the ways to do that is by requiring all vehicles with internal combustion engines to pass an emissions test.  That’s because these vehicles can be big polluters.  

Everyone wants their car to pass the test so they can continue their day-to-day driving routine.  But then comes that one day when they tell you your vehicle has failed.  Why does that happen?

One of the most common reasons is that your gas cap is leaking or loose (or maybe you don’t even have one on your vehicle!).  The gas cap is supposed to seal in vapors, but sometimes its seals or gaskets dry out or crack. Replace it, and you’re good to go.

Another common reason your vehicle failed the test is that your catalytic converter isn’t doing its job. It is supposed to convert toxic gases from your engine into ones that don’t pollute the air.  There are many reasons the catalytic converter may not be working.  It may be physically damaged, or the steady flow of exhaust gases has fouled the converter. 

You may have a bad oxygen sensor. It’s supposed to measure how much oxygen is in your exhaust.  This can cause the air-fuel mixture to be too rich, resulting in too many hydrocarbons in the exhaust. Your ignition system may also have problems, such as worn-out spark plugs.  Dirty fuel injectors can contribute to excess emissions.

Believe it or not, a dirty engine air filter may be the culprit. If it hasn’t been replaced for a while, your vehicle may be emitting too many hydrocarbons -  something that will cause your vehicle to fail the emissions test.

You can usually avoid a failed emissions test by maintaining your vehicle regularly.  The best way to do that is by bringing it to our trained technicians, so your vehicle gets the service it needs, scheduled and non-scheduled.  Plus, you’ll be doing your part to keep our air clean.

Tuffy Richmond
3473 COUNTY LINE RD
CASCO, WI 48064
5865001414

More articles from Tuffy Richmond

Tuffy Richmond Brake Service for Safe Stopping in CASCO

November 10, 2024

Let's talk about something critical for all CASCO drivers: your brakes. Your vehicle is heavy, and it takes a lot of muscle to bring it and your passengers to a safe stop so everything needs to be in good working order. Here's an explanation on how your disc brakes work: The wheel hub keeps your... More

U and your U-Joints (Lubricate U-Joints)

November 3, 2024

If your vehicles power goes to the rear wheels, then you have something called U-joints in the drivetrain. U-joints are connectors that allow the rotating power from your vehicles engine to deliver its power through a driveshaft to make the rear wheels rotate. You need U-joints because the surfa... More

Before You Buy that Used Vehicle (Having a Used Car Inspected Before Buying)

October 27, 2024

Let's face it. New vehicles are expensive, so finding a good used one can save drivers a lot of money. It's tempting to look through ads, find a private seller who has what you're looking for and pay a price you think is a great deal. But when you go over to look at a used car, do you really k... More