Wisconsin Vehicle Inspection Program - 2005-2006 Annual Report

IM240 Failure Rate By Model Year

Model Year	2007	2008	Model Year	2007	2008	Model Year	2007	2008
1968	28%	36%	1981	37%	32%	1994	14%	22%
1969	47%	37%	1982	28%	35%	1995	16%	11%
1970	37%	35%	1983	30%	23%	1996	17%	27%
1971	27%	18%	1984	23%	28%	1997	17%	14%
1972	30%	18%	1985	31%	22%	1998	9%	17%
1973	32%	22%	1986	18%	23%	1999	10%	6%
1974	24%	20%	1987	39%	31%	2000	5%	10%
1975	43%	26%	1988	26%	38%	2001	4%	3%
1976	26%	41%	1989	34%	23%	2002	2%	2%
1977	42%	24%	1990	24%	34%	2003	2%	1%
1978	30%	37%	1991	30%	23%	2004	1%	1%
1979	36%	25%	1992	21%	30%	All	19%	17%
1980	26%	24%	1993	25%	19%

Idle Failure Rate By Model Year

Model Year	2007	2008	Model Year	2007	2008	Model Year	2007	2008
1968	29%	50%	1980	27%	20%	1992	17%	31%
1969	25%	39%	1981	57%	29%	1993	19%	14%
1970	46%	33%	1982	38%	50%	1994	12%	17%
1971	32%	40%	1983	11%	36%	1995	16%	11%
1972	40%	13%	1984	41%	44%	1996	8%	6%
1973	52%	0%	1985	38%	30%	1997	7%	12%
1974	43%	29%	1986	38%	32%	1998	4%	7%
1975	36%	22%	1987	29%	34%	1999	12%	7%
1976	38%	22%	1988	19%	30%	2000	2%	5%
1977	27%	56%	1989	15%	26%	2001	0%	2%
1978	40%	18%	1990	19%	27%	2002	0%	0%
1979	45%	32%	1991	27%	22%	2003	0%	2%
						2004	0%	0%
						All	13%	12%

Gas Cap Failure Rate By Model Year

Model Year	2007	2008	Model Year	2007	2008	Model Year	2007	2008
1971	37%	14%	1982	10%	10%	1994	4%	6%
1972	20%	18%	1983	13%	8%	1995	5%	4%
1973	35%	19%	1984	8%	9%	1996	4%	6%
1974	16%	22%	1985	8%	6%	1997	4%	4%
1975	13%	7%	1986	6%	9%	1998	3%	4%
1976	14%	14%	1987	7%	5%	1999	4%	3%
1977	14%	9%	1988	5%	6%	2000	3%	4%
1978	11%	13%	1989	6%	5%	2001	3%	3%
1979	17%	9%	1990	5%	7%	2002	2%	3%
1980	10%	13%	1991	5%	5%	2003	2%	2%
1981	9%	6%	1992	4%	6%	2004	3%	3%
			1993	5%	4%	ALL	3%	3%

Average Repair Costs By Model Year (All Test Types)

Model Year	2007	2008	Model Year	2007	2008	Model Year	2007	2008
1968	$80	$0	1981	$173	$171	1994	$373	$403
1969	$438	$130	1982	$282	$278	1995	$355	$350
1970	$449	$100	1983	$270	$614	1996	$322	$349
1971	$116	$250	1984	$339	$311	1997	$355	$414
1972	$277	$127	1985	$384	$265	1998	$331	$368
1973	$205	$85	1986	$315	$269	1999	$370	$376
1974	$65	$179	1987	$326	$385	2000	$341	$364
1975	$232	$107	1988	$326	$318	2001	$319	$298
1976	$347	$642	1989	$317	$349	2002	$291	$308
1977	$275	$298	1990	$313	$333	2003	$276	$328
1978	$179	$171	1991	$345	$342	2004	$132	$203
1979	$331	$278	1992	$334	$365	2005	$152	$76
1980	$245	$0	1993	$319	$348	ALL	$288	$297

Cost Waivers by Model Year

Model Year	2007	2008	Model Year	2007	2008	Model Year	2007	2008
1968	3	1	1982	8	1	1996	23	9
1969	7	2	1983	1	3	1997	5	4
1970	4	0	1984	11	1	1998	4	7
1971	1	0	1985	6	5	1999	9	1
1972	2	0	1986	17	2	2000	4	3
1973	2	1	1987	24	26	2001	1	3
1974	3	1	1988	78	12	2002	1	0
1975	1	0	1989	41	22	2003	0	0
1976	2	0	1990	103	21	2004	0	0
1977	7	1	1991	48	40	2005	0	0
1978	7	1	1992	139	37	2006	0	0
1979	3	3	1993	66	62	2007	0	0
1980	4	1	1994	173	36	All	864	361
1981	3	0	1995	53	55

Operating Statistics | Volumes By Test Type | Customer Convenience | Failure Statistics | Tailpipe Tests - IM240 & Idle

Operating Statistics

Test Volume

In 2008, the test volume was 629,359 tests. The dramatic drop in test volume was a result of program changes, which occurred in July 2008. The changes that affected testing volume included: 1) eliminating 1968- 1995 vehicles from the testing requirement; and 2) eliminating heavier duty vehicles (>8,500 GVWR) from the testing requirement. In addition the closing of Waukesha South, affected the volume comparisons between stations. The highest volume station remained West Allis and the lowest volume station remained Burlington.

Operating Statistics	2007	2008
Total Tests	749,906	629,359
# of Registration Renewal Tests	605,743	541,390
# of Change of Ownership Tests	141,114	102,850
Highest Volume Station	Milwaukee South 94,545	West Allis 73,498
Lowest Volume Station	Burlington 23,289	Waukesha South 16,243

Test Station Activity - Total Volume

The year-to-year comparisons reflect the reduction of stations from 12 to 11, with the closing of Waukesha South, as well as the reduction of the testing fleet. West Allis was the station with the highest volume in 2008. Waukesha South was the least busy station, with only 16,243 tests for the 6 months it was open. One anomaly caused by the closing of the Waukesha South facility was the one percent increase in testing volume for Waukesha North, while the entire network lost volume by 19%. In spite of the reduction in the testing fleet, Waukesha North was the only station to gain testing volume in 2008 as a result of being the closest alternate testing site for Waukesha South.

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Volumes By Test Type

Prior to July 1, 2008 there were several different types of test performed on the vehicle fleet, depending upon vehicle age and design. The following is a brief description of the test types:

IM240: Most pre-1996 model year vehicles received the IM240 test. This inspection involves driving the vehicle on a chassis dynamometer while sampling the vehicle’s exhaust for hydrocarbon, carbon monoxide and nitrogen oxide (NOX) emissions. It is referred to as the IM240 inspection because the vehicle is driven 240 seconds to simulate a short drive with an average speed of 29.4 mph and a top speed of 56.7 mph.

Idle: In this inspection, a vehicle’s tailpipe emissions are sampled while the vehicle is at idle. The vehicle emissions measured are hydrocarbon and carbon monoxides to determine a pass/fail decision. The vehicle’s emission equipment is also visually inspected to ensure it is still present on the vehicle.

On-Board Diagnostics

Vehicles that are 1996 and newer will receive an OBD inspection. Today's vehicles have OBD computers that monitor the vehicle's engine and emission control system. When the computer detects a malfunction, a light on the dashboard is illuminated and a code identifying the malfunction is stored in the computer for access by a repair technician. By identifying specific malfunctions, OBD enhances the repair industry's ability to diagnose and repair vehicles.

Gas Cap Tests

Prior to July 1, 2008, all vehicles model year 1972 and newer received a gas cap inspection to ensure that their vehicle’s gas cap sealed properly. This test was discontinued in July because newer vehicle’s OBD systems also monitor the vehicles fuel system for leaks.

As discussed earlier, as of July 1, 2008, the only type of inspection offered is the OBDII inspection. As a result, only the OBDII inspections increased in 2008 as a result of the program changes. This table represents pass and fail inspections for the different tests offered in 2007 and 2008.

Volumes By Type	2007	2008
IM240 Tests	201,615	90,984
Idle Tests	7,822	4,455
OBDII Tests	481,190	501,974
Gas Cap Tests	642,163	314,612

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Customer Convenience

Waiting Times

Customer convenience is a program priority. The amount of time motorists wait for vehicle testing is a key measure of convenience because it directly affects their acceptance of the program. The vehicle inspection program has developed procedures to ensure that customer wait times are minimized. On average, customers waited slightly over 5 minutes for a test in 2008.

As the chart illustrates, the waiting time dropped dramatically with the test volume in July when the program changes were implemented. The OBDII test is a much shorter test and built in efficiencies in the testing process reduce the waiting time for motorists.

The busiest month in 2008 was March, with an average waiting time of 7:54 minutes and a test volume of 70,059 vehicles. The least busy month was December with an average waiting time of 4:27 minutes and a test volume of 37,798 vehicles.

Customer Service

Periodically a survey questionnaire is distributed to motorists over a 4-6 week time period to determine motorist’s level of satisfaction with the customer service at each inspection station. The questionnaire, distributed in late July and August, asked motorists to rate various customer service aspects including the station appearance, inspector’s attitude, waiting time and overall level of service. There were 1,793 surveys returned in 2008. In all service categories, 99% of the respondents rated each service area either good or excellent. The survey results reaffirmed that motorists are satisfied with the level of service they receive at the inspection stations.

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Failure Statistics

Overview

A small population of vehicles in southeastern Wisconsin produces most of the vehicle exhaust pollution – these are the so-called gross polluters. As vehicles are driven, problems can develop because of defective parts, improper maintenance or simply from deterioration due to age and usage. This helps explain why a vehicle can be relatively clean one year and become a gross polluter at the time of its next inspection. Since hydrocarbon, carbon monoxide and nitrogen oxides are invisible, a vehicle inspection is an effective method to ensure that a vehicle is not polluting excessively.

For the IM240 and Idle emission tests, emission limitations are simply the emission standards used to determine whether a vehicle passes or fails the emission inspection. The Wisconsin Department of Natural Resources (DNR) determines the emission standards necessary to achieve the emission reductions needed to attain air quality standards in the most cost effective manner. The emission limitations allow at least double the emission levels that vehicles should achieve if properly tuned and maintained. This helps ensure that a relatively well-maintained vehicle should be able to pass the emission test.

The following chart is a summary of the failure rates for: 1) All Test Types; 2) IM240; 3) Idle; 4) OBDII and 5) Gas Caps. It also lists the associated repair costs for each test type. The average repair costs are for repairs performed at a repair facility between the initial test failure and subsequent retest pass.

	2007	2008
Volume - All Test Types (pass/fail only)	697,653	600,462
Initial Test Fail Rate – All Test Types	10%	9%
Retest Fail Rate – All Test Types	24%	20%
Overall Fail Rate	12%	9%
Avg. Repair Cost for 1st Retest Pass	$288	$297
IM240 Test Volume (pass/fail only)	201,615	90,984
Initial IM240 Fail Rate	14%	13%
Retest IM240 Fail Rate	48%	49%
Overall IM240 Fail Rate	19%	17%
Avg. Repair Costs for 1st Retest Pass	$336	$321
Idle Test Volume (pass/fail only)	7,822	4,455
Initial Idle Fail Rate	10%	8%
Retest Idle Fail Rate	47%	53%
Overall Idle Fail Rate	13%	12%
Avg. Repair Costs for 1st Retest Pass	$289	$265
OBD Test Volume (pass/fail only)	481,190	501,974
Initial OBD Fail Rate	7%	7%
Retest OBD Fail Rate	8%	11%
Overall OBD Fail Rate	7%	7%
Avg. Repair Costs for 1st Retest Pass	$285	$311
Gas Cap Test Volume (pass/fail only)	642,163	314,612
Gas Cap Fail Rate Overall	4%	3%
Vehicle Waivers (Year)	864	361

The overall failure rate for all test types fell from 12% in 2007 to 9% in 2008. The drop in the failure rate can be attributed to a number of factors, including the fact that older vehicles were exempted from the testing requirement beginning July 1st and newer vehicles generally are more durable than older ones.

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Tailpipe Tests - IM240 and Idle

IM240 Tests The overall IM240 failure rate decreased slightly in 2008, from 19% in 2007 to 17% in 2008.
Idle Tests Vehicles only received an idle inspection when the IM240 inspection or OBDII inspection cannot be performed. In addition to the idle tailpipe inspection, the vehicles receive a visual emission equipment inspection. In 2007, the overall idle test failure rate was 13% and in 2008 the overall failure rate was 12%
OBDII Tests Testing Elements On-Board Diagnostic (OBD) Inspection: Vehicles that are 1996 and newer will receive an OBD inspection. Today's vehicles have OBD computers that monitor the vehicle's engine and emission control system. When the computer detects a malfunction, a light on the dashboard is illuminated and a code identifying the malfunction is stored in the computer for access by a repair technician. By identifying specific malfunctions, OBD enhances the repair industry's ability to diagnose and repair vehicles.
Check Engine Light Bulb Test: The inspector performs a test to ensure that the vehicle's check engine light is functioning properly. This is accomplished by turning the ignition key to the on position without starting engine. The vehicle would fail this portion of the inspection if the check engine light does not illuminate.
Vehicles Rejected For OBDII Inspections Communications: The inspector will connect the testing equipment to the vehicle's onboard computer port (Diagnostic Link Connector). If the vehicle cannot communicate with the testing equipment, the vehicle will be rejected from further testing until this condition is corrected. Prior to July 1, 2008, vehicles with communication problems defaulted to the IM240 inspection. There are several factors that can cause non-communication. Some of the most common causes are: Damaged Data Link Connector (DLC): The data link connector is damaged or as been tampered with and the connection to the on-board diagnostic (OBD) computer is not possible. For example, the DLC may be broken or melted, the DLC is used to power up an accessory, or something is plugged into the DLC. Blown Fuse: If the vehicle fails to communicate, the cause may be a burned out cigarette lighter fuse. On most vehicle makes and models, the system on the vehicle that communicates with the test equipment also gets its power fro the same circuit as the cigarette lighter. Improperly Installed Aftermarket Systems: Some installers of aftermarket systems, such as radios, security systems, navigation systems, etc, are tapping into the wiring harness of the DLC, or OBD port to power the radio or other aftermarket devices. This would prevent the vehicle’s OBDII system from communicating. The following chart breaks down test communication rejects by model year that occurred at the time of the initial inspection.
Readiness Monitors: A vehicle’s OBD system continually tracks and stores information about the emission control devices and other engine related components. Readiness monitors indicate if components have been fully evaluated and whether system components have experienced any driving conditions that prevent the vehicle from operating as designed by the manufacturer. The test equipment reads the readiness monitor statuses as part of the vehicle emissions inspection. If the vehicle is in the process of resetting itself, it is said to be “Not Ready”, resulting in one or more unset readiness monitors. Vehicles “Not Ready” for OBD testing receive a reject test result. For 1996 - 2000 model year vehicles, a vehicle can have up to 2 readiness monitors unset; for 2001 and newer vehicles only 1 readiness monitor can be unset. If the unset readiness monitors exceed the requirements, the vehicle will be rejected from further testing until this condition is corrected. Some of the most common reasons for a vehicle to be not ready include: Recent vehicle repairs or maintenance in which diagnostic trouble codes have been cleared with an OBD scan tool. A recently disconnected or replaced battery The vehicle’s computer requires an update. There is a pending problem that has not yet illuminated the “check engine” light. Until July 1, 2008, vehicles which exceeded the readiness monitor criteria on their initial inspection were defaulted to a tailpipe inspection at the time of their initial inspection. The following chart indicates the number of vehicles that were rejected due to readiness monitor issues at the time of their initial inspection, beginning July 1, 2008.
Check Engine Light Commanded On: If the vehicle's check engine light is commanded on due to an emission component malfunction, then the Diagnostic Trouble Codes (DTC) are recorded and provided to the motorist. The vehicle will fail this portion of the inspection if the check engine light is commanded on. The vehicle will need to be repaired and brought back for a retest. The overall OBDII failure rate was 7.5% in 2007 and 7.4% in 2008.

Gas Cap Tests During 2006 the overall failure rate for gas cap tests averaged 3% compared to 4% for 2007. As the chart illustrates, older vehicle gas cap failure rate were much higher than newer vehicle gas cap failure rates. This increased failure rate is a result of gas cap wear and tear, which affects the way a gas cap seals on the vehicle. Without a functional gas cap pressure test, a motorist would not be aware of the problem. A gas cap that fails the pressure test would allow evaporating gas from the vehicle to enter the air. Not only is this bad for the environment but it also is bad for a vehicle’s fuel economy.
Repairs Are Effective In Reducing Emissions Most failed vehicles can be repaired and successfully pass a reinspection after the initial failure. The passing rate on the first retest is a result of a knowledgeable repair community and detailed diagnostic information that is available on OBDII equipped vehicles. For all test types, motorists whose vehicle failed an initial emissions test and passed a first retest after the vehicle received emission related repairs at a repair facility paid an average repair cost of $297 in 2007, compared to $288 in 2007.
Vehicle Waivers A motorist may request a waiver from further test requirements for the current test cycle if the vehicle fails a second retest after repairs. In general, a waiver may be granted if the motorist exceeds the cost limit on emission-related repairs and adjustments at a recognized repair facility. The waiver repair cost limit excludes emission system warranty repairs and the repair/replacement of tampered emission control devices identified during the equipment check. With vehicles equipped with OBDII systems, the MIL will not be commanded on unless the vehicle computer has determined that a component or system failure will adversely affect the emission levels of the vehicle. It is for that reason that an illuminated check engine light would prevent a vehicle from receiving a waiver. This waiver requirement was in place since the implementation of the Wisconsin Vehicle Inspection Program in 1984. Since the OBDII test is based on whether the MIL light has been commanded on, OBDII-compliant vehicles are not considered for cost waiver consideration. For that reason, the number of waivers dropped in 2008 when the program adopted the OBDII only inspection.

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