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616 Central Ave Northwood, IA, 50459
  • MON: 8:00AM - 5:00PM
  • TUES: 8:00AM - 5:00PM
  • WED: 8:00AM - 5:00PM
  • THUR: 8:00AM - 5:00PM
  • FRI: 8:00AM - 5:00PM
  • SAT: Closed
  • SUN: Closed
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8048th St North Northwood, IA, 50459
  • MON: 8:00AM - 5:00PM
  • TUES: 8:00AM - 5:00PM
  • WED: 8:00AM - 5:00PM
  • THUR: 8:00AM - 5:00PM
  • FRI: 8:00AM - 5:00PM
  • SAT: Closed
  • SUN: Closed
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Smog Checks in Worth County

Smog Checks in Worth County

*Please bring your DMV renewal notice indicating a Smog Check is required with you and your Smog Check certificate will be electronically sent to the DMV.

Worth County's Trusted Source for Smog Testing and Repair

Since 2013, the pro mechanics at Knudtson Automotive Services have provided quick smog testing and cost-effective smog repairs when needed. Start a maintenance service plan with us that can help prevent high-cost repairs to your emission system. We are professional, honest, and friendly. For five star, cost conscious smog testing and repair services schedule an appointment today or stop by one of our locations.

How to Know If You Need an Emissions Test

Emissions testing is a mandatory requirement during the initial vehicle registration process and subsequently every few years in many cases. To renew your registration, most states insist on your vehicle undergoing emissions testing every one or two years. Nevertheless, the frequency of these tests can vary based on your state's regulations, so it's advisable to check with your local Department of Motor Vehicles (DMV) to determine the specific requirements in your area. Additionally, if you plan to sell your vehicle or transfer its title to another person, you may also be required to undergo an emissions test.

Getting your emissions tested is typically a straightforward and swift process, readily available at most auto repair shops or state-operated testing centers. Appointments are often unnecessary; you can usually walk in and have your vehicle tested. However, if you have concerns about your vehicle's chances of passing the test, it's a good practice to call ahead and confirm that the testing center has the appropriate equipment for your specific vehicle.

How Long Does a Smog Check and Inspection Take?

The duration of a smog check and inspection can vary depending on several factors, including the specific testing procedures, the type of vehicle being inspected, and the efficiency of the testing facility. Typically, a standard smog check and inspection for most vehicles can take anywhere from 20 to 30 minutes.

However, if the vehicle requires additional diagnostics or repairs to meet the required emissions standards, the overall process may take longer. In such cases, the time taken for the smog check and inspection can extend to an hour or more, depending on the complexity of the issues that need to be addressed.

What Does Knudtson Automotive Services Do During a Smog Check?

We inspect your car or truck's emissions-control equipment to measure the number of pollutants your vehicle is emitting.

1. First, our experienced mechanics will analyze your car or truck's OBD computer system, emissions-control system, and check engine light codes for standard warnings that your emissions system is no longer functioning properly.

2. Next, we will inspect your car or truck's gas cap, ignition timing, exhaust gas recirculation system, fuel, and evaporative system.

3. Finally, we will perform a Tailpipe Emissions Inspection which measures the type and quantity of any pollutant emitted from your vehicle's tailpipe.

Why Choose Knudtson Automotive Services in Worth County for Your Smog Testing and Repair

  • Specialized smog check service station in Worth County
  • Smog test and repair options to minimize cost and maximize convenience
  • Smog failure diagnosis with onsite repair and smog retesting
  • State-of-the-art automotive smog repair systems and tools
  • We participate in the California State Free Smog Testing Program
  • Ask about smog repair discounts and coupons

Did You Pass Your Smog Test?

Great! If your vehicle passes a smog check, Knudtson Automotive Services will provide you a vehicle inspection report showing your vehicle's results and will electronically send the smog certificate to DMV.

Smog Check Repairs
What do I do if my car fails the smog test? At Knudtson Automotive Services we will work with you to make the needed repairs to help your car pass the smog test and get your certificate.
Learn more about smog check repairs

Smog Testing vs. Emissions Testing
Sometimes customers refer to smog as emissions testing, but they are not the same. Each test measures different levels of hydrocarbons, oxygen, carbon monoxide, and oxides.

Learn about the difference between smog testing and emissions testing

Discover More About Exhaust Repair Services At Knudtson Automotive Services in Northwood

Learn more about Smog Checks vs Emissions Testing
Undercar Services: Maintenance


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Pulled off the freeway the day after Christmas. Got immediate help to fix a tire to get me home. Excellent and friendly staff.

Knudtson Automotive Services

Knudtson Automotive Services - South 616 Central Ave Northwood, IA 50459 641-324-9988
Knudtson Automotive Services - North 8048th St North Northwood, IA 50459 641-324-2652

Ask any car or truck owner in Worth County who they recommend. Chances are they will tell you Knudtson Automotive Services.