Failed Vehicles
A failed test result means your vehicle has not met U.S. Environmental Protection Agency emissions standards. Because emissions from a failing vehicle contribute to ozone formation, additional repairs are necessary until the vehicle passes, or until all requirements for a cost-based waiver are met. For more information see Waiver Criteria.
New Extension Option for Unset Readiness Monitors
Beginning Aug. 28, 2008, motorists whose vehicles fail the OBD test only because the vehicle's readiness monitors are unset are now legally permitted to drive their vehicle for up to 30 days beyond the expiration of their vehicle's registration for the purpose of resetting the vehicle's readiness monitors. Motorists should keep a copy of the most recent failing OBD test results with them to present to law enforcement officers as proof that they are operating the vehicle to reset the vehicle's readiness monitors. Even though this new law does give motorists additional time to complete their vehicle emissions inspection, the department recommends that motorists begin the vehicle emissions inspection process as soon as they receive their vehicle registration renewal notice so that they can register their vehicle on time and avoid the late registration penalty.
Repair Your Vehicle
Where can I go to have my vehicle repaired?
Anyone may perform necessary repairs for the vehicle. Customers are not required to have repairs completed at the station that performs their vehicle’s emissions test. It is important to note that waiver criteria may affect where a motorist chooses to have repairs performed. For more information see Missouri Recognized Repair Technician.
Repair Tips
Check your vehicle’s warranty.
Your repairs might be covered by a manufacturer’s warranty. For details, consult your vehicle owner’s manual or contact a dealership.
Find a repair technician.
Anyone may repair your vehicle. Customers are not required to have repairs completed at the station that performs their emissions test. However, labor costs can only be applied toward a cost-based waiver if the work was completed by a Missouri Recognized Repair Technician, since these technicians meet industry-recognized standards for emissions-related repair knowledge. For a current listing of shops employing a Missouri Recognized Repair Technician, see the Repair Facility Performance Report.
Bring the paperwork.
After the emissions test you received a Vehicle Inspection Report. Give these papers to your repair technician and make sure whomever performs the repairs correctly fills out and signs a Repair Data Sheet. Your vehicle will not be retested without this information.
Talk with your repair technician.
He/she should diagnose what’s wrong, discuss the repairs your vehicle needs, and make sure you get the most effective repairs for the money spent. Finally, remember to talk about how the repair technician can confirm that your vehicle’s readiness monitors are reset to ready.
Retesting Tips
If your vehicle has been repaired, it’s time to get ready for a retest. Retests are required until your vehicle passes or until you obtain a cost-based waiver from the Missouri Department of Natural Resources.
Know your time limits.
Once repairs are completed, the motorist must return to the initial testing station within 20 business days to qualify for one free reinspection. After 20 business days, you will be required to pay the full emissions test fee again.
The vehicle owner must present to the station the previous vehicle inspection report and the completed repair data sheet that your repair technician filled out and signed. Your passing emissions test is valid for registration purposes for 60 days from the date the vehicle passes the test or receives a cost-based waiver.
Before you retest…
Drive your repaired vehicle normally for several days before returning to the station that initally performed the emissions test. Doing so can help reset your vehicle’s readiness monitors. For more information see readiness.
Diagnostic Trouble Codes
What are Diagnostic Trouble Codes?
Diagnostic Trouble Codes are vehicle generated-OBDII codes that can trigger a malfunction indicator light. Each numeric code corresponds with a specific emissions-related concern. All emissions system components that caused Diagnostic Trouble Codes to appear must be repaired in order for the vehicle to pass.
The Vehicle Inspection Report provided at time of failure will list the Diagnostic Trouble Codes recorded from the vehicle’s OBDII computer. Not
all Diagnostic Trouble Codes that trigger the MIL may be listed on the Vehicle Inspection Report. Manufacturer specific Diagnostic Trouble Codes (P1###) are listed, but not defined, on the Vehicle Inspection Report as the definitions vary between manufacturers.
You should not replace emissions control components based solely on the Diagnostic Trouble Codes stored in the vehicle’s OBDII system.
A proper diagnosis by an OBDII trained or experienced technician is needed to positively identify the cause(s) of the current OBDII test failure.
Repair technicians may choose to clear the Diagnostic Trouble Codes electronically after the repair. This process will reset the emissions system monitors to Not Ready. Your repair technician should assist you in taking the necessary steps to reset the monitors to Ready.
On the other hand, repair technicians may choose to perform a repair and then leave the Check Engine light illuminated. After the vehicle performs the required drive cycles to verify that the condition causing the Diagnostic Trouble Code hasn’t reoccurred, the OBDII system will turn the Check Engine light off. You can then return to the station for an emissions retest.
Before your vehicle can be retested, all required emissions system monitors must have a Ready status noted. Please discuss with your repair technician about how you can tell when your vehicle is ready to be retested.
Waiver Criteria
Yes, there are three waivers offered to vehicle owners that fail the emissions test. The waivers include cost-based, out-of-area and reciprocity.
Cost-based emissions waivers are available if a motorist has spent more than $450 on emissions-related repairs and labor. However, labor costs can only apply toward the waiver amount if a Missouri Recognized Repair Technician performs the repairs. If the vehicle owner performs the repairs, the owner must spend at least $400 in qualified emissions-control parts, as determined by the EPA, toward the waiver amount. See the Cost-Based Waiver Applications below.
If vehicle owners are financially dependent solely on state and federal disability benefits or other public assistance programs and anticipate failing the emissions test, they may receive a waiver. The vehicle owner must provide reasonable and reliable proof to the department 30 days in advance of their vehicle’s anticipated failure. The vehicle owner must spend at least $200 on emissions-related repairs and labor to qualify. See Financial Waiver Eligibility Request to determine your eligibility.
Out-of-area waivers are also available. If a vehicle is registered in the St. Louis ozone nonattainment area, but operating outside of that area for the next 24 consecutive months, owners may apply to the department for an out-of-area waiver. See Out of Area Declaration Form 4902 to apply.
Finally, reciprocity waivers are available. If a vehicle is in a state other than Missouri and that state conducts pass/fail OBD testing, the motorist may choose to have the vehicle emissions inspected in that state and submit a reciprocity waiver application to the department.
If a vehicle is in a state other than Missouri, the motorist may also choose to have the vehicle emissions inspected in Missouri within 10 days of the vehicle returning to the state. To submit evidence that the vehicle was out of state, the applicant can print Department of Revenue General Affidavit Form 768. Check Box 3 of this General Affidavit, fill out the vehicle information section, and submit this form with the registration renewal application directly to the Department of Revenue.
Vehicle owners must apply for all emissions waivers with the Missouri Department of Natural Resources. Vehicle owners may write to Missouri Department of Natural Resources, Gateway Vehicle Inspection Program, 7545 S. Lindbergh, Ste. 210, St. Louis, MO 63125 or call 314-416-2115.
For more information see Waiver Criteria and Frequently Asked Questions About Emissions Waivers PDF
Waiver Applications and Exemption Requests
Once a request is received, motorists will be notified in writing of the approval or denial of their request. If the request is approved, the motorist will not be required to take further action as the department will notify DOR electronically of the approval. If the request is denied, then the motorist will be required to have their vehicle emissions tested. The department is not responsible for any penalties associated with late registration due to failure to submit an exemption or waiver request in a timely manner.
Cost-Based Waiver Application Affidavit - Repairs Made by a Repair Technician, MO 780-1971 Fill-in MS Word DOC / Adobe PDF
For more information see Missouri Recognized Repair Technician.
Cost-Based Waiver Application Affidavit - Repairs Made by a Vehicle Owner, MO 780-1973 Fill-in MS Word DOC / Adobe PDF
Estimate-Based Waiver Application Affidavit, MO 780-1994 Fill-in Word DOC / Adobe PDF
Mileage-Based Exemption Request, MO 780-1972 Fill-in MS Word DOC / Adobe PDF
Financial Waiver Eligibility Request, MO 780-1970 Fill-in MS Word DOC / Adobe PDF
For more information see Frequently Asked Questions About Emissions Waivers PDF
