Vehicle Aging and Comparative

Emissions Testing Using E0 and E15 Fuels

Evaporative Emissions Results

NREL Subcontract JGC-9-99141-01

August 31, 2010

Environmental Testing Corporation

Aurora, Colorado

Keith Vertin, (303)365-7849, kvertin@etclab.com

Tom Beierschmitt

Environmental Testing Corporation is an accredited laboratory, in compliance with ISO 

14001:96, and ISO 17025-1999 for performing vehicle and engine emissions tests. 

American Association for Laboratory Accreditation Certificate Number 1975-01.
Topics

 Test Approach

– Objective

– Vehicle preparation and canister loading

 Evaporative Emissions Results

– 2 day diurnal 

– Honda Odyssey repeat testing

– Comparison to EPA standard
Evaporative Emissions

Background Information

 ETC was contracted by DOE/NREL to age eight vehicles to 120000 miles, and to 

perform periodic exhaust emissions tests

 ETC contributed SHED testing to the project, to also get some comparative 

information about the evaporative emissions from E0 and E15-fueled vehicles

 2-day diurnal evaporative emissions tests were performed following the triplicate 

FTP75 exhaust emissions tests, at 4000, 60000, 90000 and 120000 mile events

 Four vehicles were aged on E0 fuel and four aged on E15 fuel, using mileage 

accumulation dynamometers. Since the vehicles accumulated about 1000 miles 

per day during 24/7 aging on the MADs, the evaporative emissions system was 

not exercised as it would be in real-world driving

– Far fewer refuel, diurnal, and purge cycles

– Shorter duration of fuel exposure

 But the test approach provides some timely, 

comparative data on evaporative emissions from E0 and E15 fuels
2009 Model Year Vehicles

Ford Focus, 2.0L, Tier 2 Bin 4 Toyota Camry, 2.4L,Tier 2 Bin 5

Honda Odyssey, 3.5L, Tier 2 Bin 5 Saturn Outlook, 3.6L, Tier 2 Bin 5

4 vehicles aged using E0 fuel, 4 vehicles aged on E15 fuel
Test Approach

 Evaporative emissions run per Federal Test Procedure Supplemental Evaporative 

Test (“2-Day Diurnal” sequence)

 Windshield washer bottles drained and flushed, vehicles washed, no vehicle 

baking, vehicles had newer tires

 All vehicles were SHED tested after approximately 4000 miles of run-in, on high 

altitude certification E0 fuel (40CFR86.113-04)

 One vehicle from each pair was then refueled on certification E15 fuel (fuel grade 

ethanol splash blended in certification E0 fuel)

 Conditioning after initial fuel change to certification E15:

– Approximately 1000 miles using Standard Road Cycle

– Certification E15 fuel was in tank for approximately 2 months before exhaust emissions 

and SHED testing (September to November/December 2009) 

– E15-fueled vehicles then retested in SHED using certification E15 fuel at approximately 

5400 miles
Test Approach, continued

 For E0 control vehicles at mileage intervals of 60000, 90000 and 120000 miles:

– Control vehicles aged on E0 road fuel and switched to high altitude 

certification E0 fuel for last 500 miles of each interval

– SHED testing performed using certification E0 fuel after triplicate exhaust 

emissions tests were completed

 For E15 test vehicles at mileage intervals of 60000, 90000 and 120000 miles:

– Test vehicles aged on splash-blended E15 and switched to cert E15 fuel (fuel 

grade ethanol blended in cert E0 fuel) for last 500 miles of each interval

– SHED testing performed using cert E15 fuel after triplicate exhaust emissions 

tests completed, and before fuel change to cert E0 fuel
Test Considerations

 The RVP of the fuels are different, ethanol increases the RVP 

– High altitude Cert E0 fuel RVP was 7.89 psi (typical)

– Cert E15 fuel RVP was 8.65 psi (typical)

 The “aftermarket” fuel drain hose used to aid fuel drain and fills (shown below) 

was removed prior to the prep cycle for all SHED testing as these hoses are 

permeable. The fuel supply hose connection was returned to stock configuration 

prior to each prep cycle.

 Vehicles do not have service ports, so canisters were butane-loaded through a 

modified gas cap as shown on next slide.

To Rail

From Tank
Gas Cap Modification for Canister Loading

Inner white piece has sealing function

and continues to turn freely relative to 

black handle (ratcheting action works as normal)

Cured epoxy

seal prevents 

leakage past 

bulkhead fitting

1⁄4” tube through bulkhead fitting, 

the fitting is mechanically fastened 

to inner white piece

Swagelok seals tube to

bulkhead fitting

Black handle modified for bulkhead 

fitting nut and washer, positively 

clamping fitting to inner white piece

Gas Cap Modification for Canister Loading

Used only for Canister Loading

Standard vehicle cap to be used for all other procedures
Ford Focus 2-Day Diurnal Results

 Day 1 and Day 2 evaporative emissions very similar

 The 90000 mile SHED test for vehicle #128417 was skipped due to project time 

constraints

Control Vehicle #128416, E0 Fuel

0

0.1

0.2

0.3

0.4

0.5

Start (4k-5k) 60k 90k 120k

Eavp Emissions (g/day)

Nominal Odometer (miles)

Day 1

Day 2 N/A

0

0.1

0.2

0.3

0.4

0.5

Start (4k-5k) 60k 90k 120k

Eavp Emissions (g/day)

Nominal Odometer (miles)

Day 1

Day 2

Test Vehicle #128417, E15 Fuel
0

0.1

0.2

0.3

0.4

0.5

Start (4k-5k) 60k 90k 120k

Eavp Emissions (g/day)

Nominal Odometer (miles)

Day 1

Day 2 N/A

0

0.1

0.2

0.3

0.4

0.5

Start (4k-5k) 60k 90k 120k

Eavp Emissions (g/day)

Nominal Odometer (miles)

Day 1

Day 2

Toyota Camry 2-Day Diurnal Results

 Day 1 and Day 2 evaporative emissions were similar

 The 60000 mile test for vehicle #128419 was voided

 Evaporative emissions for vehicle #128418 and some other vehicles were higher at 

4000 miles than at 60000 miles

– Possible explanation is vehicle and tire off-gassing but this was not quantified

Control Vehicle #128418, E0 Fuel Test Vehicle #128419, E15 Fuel
Honda Odyssey 2-Day Diurnal Results

 Day 1 and Day 2 evaporative emissions were similar

 Omitted tests for E15-fueled vehicle #128415:

– at 60000 miles, test possibly impacted by split fuel tank filler hose

– at 90000 and 120000 miles, tests impacted by split fuel tank filler hose

 Retest at 120000 miles after fuel tank filler hose replacement, using cert E0 fuel

– cert E0 in fuel tank about 6 weeks prior to retest

Control Vehicle #128414, E0 Fuel Test Vehicle #128415

0

0.1

0.2

0.3

0.4

0.5

Start (4k-5k) 60k 90k 120k

Eavp Emissions (g/day)

Nominal Odometer (miles)

Day 1

Day 2 N/A N/A

0

0.1

0.2

0.3

0.4

0.5

Start (4k-5k) 60k 90k 120k

Eavp Emissions (g/day)

Nominal Odometer (miles)

Day 1

Day 2

E15 Fuel

E0 Fuel
Honda Odyssey #128415

Fuel Tank Filler Hose Issue

 Hose is not in an area where vehicle is handled or strapped

 Split in hose was found by dripping fuel during drain and fill at 120000 miles

 ETC does not have plausible theory on how hose was split

Location of 

Split in Hose

Fuel Tank
Saturn Outlook 2-Day Diurnal Results

 Day 2 evaporative emissions significantly higher than Day 1 emissions, for both 

vehicles

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Start (4k-5k) 60k 90k 120k

Eavp Emissions (g/day)

Nominal Odometer (miles)

Day 1

Day 2

0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

Start (4k-5k) 60k 90k 120k

Eavp Emissions (g/day)

Nominal Odometer (miles)

Day 1

Day 2

Control Vehicle #128420, E0 Fuel Test Vehicle #128421, E15 Fuel
Supplemental Evaporative Test Results

 2009 EPA Standard (Phase In): LDV = 0.65 g/test, LDT = 0.85 g/test

Highest Day + 1 Hr Hot Soak

 Vehicles met the standard on both fuels

N/AN/AN/AN/A

0.0

0.2

0.4

0.6

0.8

1.0

Start (4k- 5k)

60k90k

120k

Start (4k- 5k)

60k90k

120k

Start (4k- 5k)

60k90k

120k

Start (4k- 5k)

60k90k

120k

Mass (Highest Day + 1 hr Hot Soak), g/test

E0 Contol Vehicle

E15 Test Vehicle

Focus Camry Odyssey Outlook

2009 EPA LDV Std

2009 EPA LDT Std
Summary

 SHED testing was performed to provide some timely, 

comparative data on vehicle evaporative emissions from E0 

and E15 fuels

 Test approach does not claim to represent “real world” 

operation of the evaporative emissions control system

– Accelerated vehicle aging on mileage accumulation dynamometers had far 

fewer refuel, diurnal, and purge cycles

– Shorter duration of fuel exposure

 Supplemental evaporative emissions results for all tests were 

under the 2009 Tier 2 federal standard