Volatility Related DRIVEABILITY Concerns Service Tip (98-26-2)

Publication date: 1999-01-04
Reference number: 98-26-2
Supersedes refnos: 94-12-3, 96-5-4

VOLATILITY RELATED DRIVEABILITY CONCERNS SERVICE TIP

TECHNICAL SERVICE BULLETIN

Reference Number(s): 98-26-2, Date of Issue: January 4, 1999
Superceded Bulletin(s): 96-5-4, Date of Issue: February 26, 1996, 94-12-3, Date of Issue: June 15, 1994

NOTE: This bulletin supersedes the following Technical Service Bulletins:

96-5-4 dated February 26, 1996
94-12-3 dated June 15, 1994

DESCRIPTION

FUEL - INFORMATION ON GASOLINE - TIPS TO RESOLVE VOLATILITY RELATED DRIVEABILITY CONCERNS

APPLICATION

Model(s): Ford: 1985-97 Thunderbird

1986-99 Mustang, Taurus

1987-99 Escort

1988-94 Tempo

1989-97 Probe

1990-99 Crown Victoria

1992-93 Festiva

1995-99 Contour

Lincoln-Mercury: 1985-97 Cougar

1986-92 Mark VII

1986-99 Sable

1987-89 Tracer

1988-94 Topaz

1988-99 Continental

1990-99 Grand Marquis, Town Car

1991-99 Tracer

1993-98 Mark VIII

1995-99 Mystique

1999 Cougar

Light Truck: 1986-97 Aerostar

1987-96 Bronco

1989-97 F Super Duty, F-350

1989-99 F-150, F-250 LD, Ranger

1991-99 Explorer

1992-99 Econoline

1993-99 Villager

1995-99 Windstar

1997-99 Expedition, Mountaineer

1998-99 Navigator

1999 Super Duty F Series

Medium/Heavy Truck: 1990-97 F-700

ISSUE

Some vehicles using winter blend fuels may exhibit a stall on start up and a no restart, hard start condition or a no start condition in unseasonably hot weather (greater than 27°C/80°F). These concerns may be related to fuel volatility from winter blend fuels during winter-spring and autumn-winter transitions and may result in a fuel pump vapor lock condition. This condition may appear to be a fuel pump failure but may be caused by winter blend fuel.

ACTION

Refer to the following text for further information.

NOTE: Fuel tank additives will not resolve these concerns because vapor forms from cavitation within the fuel pump. Filling the tank to full may be effective. Advise customer to use the recommended octane grade per owner manual and not a higher grade.

Explain to the customer that this concern may be due to a low tank level of winter blend fuel combined with unseasonably warm weather. Advise customer that filling the fuel tank to full may be effective in resolving this concern. Also, advise customer to use the recommended octane grade per their Owner Manual and not a higher grade.

BACKGROUND

Gasolines are seasonally adjusted, meaning they have higher volatility (vaporize easier) in the winter and lower volatility in the summer. Government mandates to improve air quality have resulted in significant changes to gasolines, such as the mandatory use of oxygenates (ethanol, methyl tertiary butyl ether (MTBE), and others) in the winter or the reduction of Reid Vapor Pressure (RVP) in the summer. The addition of oxygenates (especially ethanol) increases volatility while the reduction of RVP reduces volatility.

Gasoline distribution practices often do not allow branded marketers to have much control over their gasoline's volatility other than RVP. Oxygenate (e.g., ethanol, MTBE) use is more dependent on local gasoline markets, rather than specific marketers practice. Therefore, it is difficult to recommend specific brands to avoid volatility related complaints.

WARRANTY INFORMATION

WARRANTY STATUS: Information Only.

OASIS CODES: 402000, 404000, 602300, 603300, 607000, 607400, 608000, 608400,609000, 609400, 610000, 611000, 611500, 612000, 614000, 614500, 623000

Volatility Related DRIVEABILITY Concerns Service Tip (98-26-2)