DEVELOPMENT OF A CHASSIS BASED INSPECTION AND MAINTENANCE PROGRAM FOR HEAVY-DUTY DIESEL POWERED VEHICLES California Environmental Protection Agency Air Resources Board 13th CRC On-Road Vehicle Emissions Workshop San Diego, California April 2003 Presented by: Donald J. Chernich

SIP Commitment/ M17 Project Goals Emission Reductions - TPD in SCAB (Southern CA) As a result of environmental law suit, the timeline for M17 was accelerated by 1 year.

Elements of SIP Measure M17  Emission reductions from in-use HDDEs  10 TPD NOx, 1 TPD ROG in SCAB 2010  Strategies to be considered  HDDE NOx field screening program  HDDE in-use compliance test program  Heavy-duty on-board diagnostic program

Development of a Field NOx Screening Test  How Would the Program Work?  Portable dynamometers set up at roadside locations  Enroute heavy-duty trucks would be detached from trailers  Emissions testing for excess NOx conducted  Repairs required for failing trucks

Stockton Laboratory Truck ready for testing. ARB staff performing power curve test.Laboratory grade emissions analyzers.Clean lab ready for next truck.

Powercurve Test Cycle Ramp Lugdown 100 hp line Analysis Region

Test Sequence Comparison  Emission results Calculated g/whp-hr, g/mi, g/gal  Modal comparison between 3 test sequence QA for Modal CO, CO 2, THC, and NOx Integrated Modal emission rate QA for integrated MPG, CO, CO 2

I/M Test Cycle Evaluation Criteria  NOx calculated in (grams/wheel hp-hour) for pre- and post-repair tests (mechanical repairs only)  g/whp-hr is a uniform matrix treats low and high hp engines equally and demonstrates repeatability within and between tests  Vehicles were sent for repairs if the pre-repair NOx g/whp-hr >8 (more repair data needed)  The test must be repeatable for a broad range of vehicles.  Cycle duration need only be as long as necessary to get a representative emission rate

Vehicle Testing Summary  91 vehicles tested  Selection designed to characterize HDD Vehicle Fleet  1550 total tests conducted  42 vehicles sent for repair

Critical Questions to Determine Value of Program 1. Are there excess NOx emissions in the vehicle population that are caused by tampering & malmaintenance? 2. Is there a practical field test that can identify those vehicles with high NOx emissions? 3. Can these excess NOx emissions be reduced through repairs and maintenance? 4. Can the reduction be made cost-effectively?

What Percentage of HDD Population can be Characterized as High NOx Emitters?  15 percent may have excess NOx Mean NOx (gwhp_hr) Percentile Percentiles Plot  Highest emitter group constitutes 5% of the population, >12 g/whp-hr.  No clear line between high and normal emitters

Effect of Repairs on NOx Emissions (g/whp-hr) NOx (g/whp-hr) Pre and Post VEH_SER_NO (2) Post-repair (1) Pre-repair Mechanical Repairs Only N = 21 Reflashes not included

Effects of Repairs (10g/whp-hr cutpoint)  3 trucks showed emissions decrease  2 trucks showed emissions increase  1 truck unchanged  Average reduction / per truck repaired:  2.1%  Approx. 3TPD reduction in South Coast  Average Repair cost: $1018

NOx Screening Program Conclusions  Current data indicates difficulty in developing a NOx screening test  Per vehicle emission reductions from repair are minimal  No clear cut point to screen out high emitters  ARB will continue to investigate magnitude and causes of high NOx emissions from HDD vehicles

Changing NOx with Time During Three Steady State Modes (NOx vs. Vehicle Power)

Baseline NOx Test Results by Model Year NOx Standard (g/bhp-hr) 6 g Std. 5 g Std. 4 g Std.

UDDS Test Data NOx vs. Model Year

UDDS Test Data PM vs. Model Year

Proof of Concept Large Scale HD I/M Program with Portable Analyzer Concept:  Use existing repair grade dynamometers and portable emissions analyzers.  An extensive network of waterbrake dynamometers exists in the state.  Simultaneous measurements with a Sensor’s SEMTECH-D emissions analyzer were collected.  CARB and SEMTECH Mass emissions computed using intake airflow meter and dyno power.

SEMTECH-D Correlation Results 1.3 g/whp-hr 15 g/whp-hr 5 g/whp-hr 610 g/whp-hr Coefficient of Variance, % of standard % CI Measurement Uncertainty, g/whp-hr – 6NA Emissions Standard g/Bhp-hr 0.04 – – – – 700 Mass Emissions Range g/whp-hr 17 – 103 ppmC 25 – 93 ppm 481 – 1385 ppm 6.1 – 7.8% Concentration Range (mean flow weighted) THCCONOxCO2

SEMTECH-D Correlation Results (Continued)  SEMTECH-D Correlation results consistent with published data.  Coefficient of Variance was less than 5% for all pollutants at applicable standards.  Exceeds EMA Task Force standards of 10%.  SEMTECH-D accuracy is suitable for a large scale I/M program.

NOx Screening Program Conclusions  Large scale I/M program with existing dynamometers and portable emissions analyzers is feasible from a technical standpoint.  Current data indicates difficulty in developing an effective NOx screening test.  Per vehicle emission reductions from repair are minimal.  There may be other unidentified engine problems that repairs did not address.  No clear cut point to screen out high emitters.  ARB will continue to investigate magnitude and causes of high NOx emissions from HDD vehicles.

Acknowledgements It is with sincere gratitude that I would like to thank all the people who helped with the development of the Stockton Laboratory and with the M17 testing effort: Mark Burnitzki, Robert Ianni, Tullie Flower, Mike Bernard, Roelof Riemersma, Brian Weitz, John Urkov, Allen Lyons, MSOD QA Section, Dipak Bishnu, Tom Cackette, Kathleen Walsh, Jim Ryden, Paul Jacobs, Chuck Owens, William Vance, Hector Maldonaldo Yvette Friend, Anise Foust, Arlene Bingaman, Lynn Pile, and Paul Loscutoff. Special Thanks to: Bell Turbo of Stockton (Barbara, Pius, Bill and Joe) DynoMaster (Rob and Lynette Youngblood) UC Riverside CE-CERT (Dr. Wayne Miller, Matt Smith, and Ted Younglove) Sensors, Inc. (Carl Ensfield, Atule Shaw, and Rob Wilson) California Analytical Inc. (Loren Mathews and Matt Swanson) Sincerely, Don Chernich The Statements and Conclusions presented are not necessarily those of the California Air Resources Board. The mention of commercial products reported herein is not to be construed as an actual or implied endorsement of such products.