1996 Bronco/F-Series

Section 03-13: Evaporative Emissions

1996 F-150, F-250, F-350, F-Super Duty and Bronco Workshop Manual

DIAGNOSIS AND TESTING

Are fuel vapor hoses or inlet blocked?

Yes	No
GO to A2.	GO to A6.

Are all system passages open?

Yes	No
REMOVE blockage or REPLACE component.	GO to A7.

Are tube or fuel vapor hoses kinked or pinched?

Yes	No
SERVICE or REPLACE tube or fuel vapor hoses. VERIFY service.	GO to A4.

Is vapor hose pinched?

Yes	No
LOOSEN fuel tank and REROUTE hose. VERIFY service.	GO to A5.

Is air passage open?

Yes	No
INSTALL evaporative emission valve in fuel tank. INSTALL fuel tank. System test complete.	REPLACE evaporative emission valve. VERIFY service.

CAUTION: Do not use other high-pressure air supplies as damage to the evaporative emissions canister may result.

Install hand pump and pressure gauge Rotunda Vacuum Tester 014-R1054 or equivalent in fuel vapor hose at test point B1.
Hand pump to a maximum of 17.2 kPa (2.5 psi).

Does pressure drop to zero immediately?

Yes	No
System flow OK. GO to A2.	PERFORM Pinpoint Test Step A3.

CAUTION: Failure to remove fuel tank filler cap may result in damage to the fuel tank.

Item	Part Number	Description
1	—	Test Point B2 with Tee
2	—	Test Point B1 with Tee
3	—	Test Point B2 Without Tee
4	9D653	Evaporative Emissions Canister
5	—	Test Point B1 Without Tee
6	—	Close Off Line
7	—	To Fuel Tank
8	9G271	Vapor Tube
9	9G297	Vapor Hose

CAUTION: Do not use other high-pressure air supplies as damage to the fuel tank may result.

Install hand pump and pressure gauge onto tee or fuel vapor canister nipple at test point B2.
Hand pump to a maximum of 17.2 kPa (2.5 psi).

Does pressure drop to zero immediately?

Yes	No
System OK, no service required.	PERFORM Pinpoint Test Step A4.