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What To Know About Texas Vehicle Emission Testing

Car having its emissions testedAre you new to Texas or even vehicle ownership in Texas? If you own a vehicle in the Lone Star State, you need to register your vehicle. In Texas, vehicle registrations and inspections are separate processes but are equally as important. The Texas Department of Motor Vehicles administers vehicle registration while DPS manages the vehicle inspection program. Before a vehicle can be registered, it must pass inspection and may require an emissions test as well.

Texas Emissions Testing

All vehicles registered in Texas are required to receive an annual inspection which includes a comprehensive safety inspection. Gas-powered vehicles aged 2 through 24 years (or upon expiration of the two-year initial inspection sticker) require an emissions test in addition to the state inspection. However, motorcycles and diesel-powered vehicles, and those living in certain counties are exempt from emissions testing.

Texas counties that require emissions testing include Brazoria, Collin, Dallas, Denton, El Paso, Ellis, Fort Bend, Galveston, Johnson, Kaufman, Montgomery, Parker, Rockwall, Travis, Williamson.

Vehicles produced in 1995 and prior will receive a Two Speed Idle Test while vehicles produced in and after 1996 will be tested via the On-Board Diagnostic test.

Two Speed Idle Test

The Two-Speed Idle test is for older vehicles that do not possess the on-board diagnostic system that cars today are equipped with. The test measures the emissions from the exhaust right from the vehicle’s tailpipe and is performed while the vehicle idles at both low and high speeds. This test is able to identify the most common factors that negatively contribute to the pollutants in the atmosphere. Vehicles emitting excessive amounts of carbon monoxide or hydrocarbons will fail the test.

On-Board Diagnostic Test

The OBDII test utilizes a scan tool that plugs directly into the vehicle’s internal computer and analyzes the data to determine whether the emissions system and its related components are working properly. Most often, if your vehicle is experiencing any sort of emissions malfunction, the internal computer will trigger the Check Engine light to come on.

Extensions & Waivers

DPS may on occasion issue an emissions testing waiver or a time extension to any vehicle that passes all necessary requirements for the standard safety inspection. An emissions testing waiver postpones the need for full compliance for a period of time after the vehicle fails the emissions test. Vehicle owners may apply once per year, per testing cycle for either a Low Mileage Waiver, Individual Vehicle Waiver, Parts Availability Time Extension, and Low-Income Time Extension. If a motorist fails the retest and decides to request a waiver, where the repairs are performed may be taken into consideration on how much the emissions-related repairs can be applied toward the waiver. All receipts and repair orders must be presented when applying for the waiver. Vehicle owners are permitted to apply for Individual Vehicle Waivers at each testing cycle.

The vehicle owner must demonstrate that they have taken every reasonable measures to meet the requirements of the vehicle emissions program and that a granted waiver will have little to no impact on air quality.

Low Mileage Waiver – Applicable to vehicles that have failed two emissions tests in the same testing cycle and at least $100 in emissions-related repairs were made. The vehicle must have been driven less than 5,000 miles from the previous inspection and intended for fewer than 5,000 before the next required safety inspection.

Individual Vehicle Waiver – Available to vehicle owners that have spent at least $600 ($450 in El Paso) on emissions repairs and is unable to pass the emission test or is unable to qualify for any other waiver. Texas DPS will approve the waiver only with confidence that granting the waiver will not significantly impact air quality.

Parts Availability Time Extension – Available to vehicle owners who are experiencing emissions failures due to difficulty obtaining a vital emissions-specific vehicle part.

Low-Income Time Extension – Available for individuals that qualify for public assistance. While this particular extension is only available once per inspection cycle, it may be granted more than once during the life of the vehicle.

Texas Annual Safety Inspection Criteria

Every passenger car and light truck will be tested to ensure all functions are working properly including:

  • Horn
  • Windshield wipers
  • Mirrors
  • Steering
  • Seat belts
  • Braking system
  • Tires
  • Wheel assembly
  • Exhaust system
  • Exhaust Emission System
  • Beam Indicator
  • Headlights
  • Taillights
  • Stop lamps
  • License plate light
  • Headlamps
  • Turn signals
  • Rear reflectors
  • Gas caps (vehicles 2-24 years old)
  • Window tinting