heavier than air. The heavier gas can displace or push fresh air out of an area. In large quantities, propane can
displace enough oxygen to make the surrounding air unfit to breathe and possibly cause illness. If a person
breathes propane gas or air that lacks oxygen due to presence of propane gas, headache, dizziness, and
weakness in the extremities can occur. In severe cases, prolonged breathing of propane-fouled air can cause
suffocation. In the event of illness from inhaling propane gas, move victim immediately to fresh air and contact
a physician or medical emergency personnel for artificial respiration or other required treatment.
DO NOT needlessly vent propane fuel during service, and do not open the 80 percent stop-fill valve while a
vehicle is inside a building. When servicing fuel system, follow recommended procedures to shut off fuel tanks
and run engine out of fuel before disconnecting fuel system components. See FUEL SYSTEM PRESSURE
RELEASE under FUEL SYSTEMS in REMOVAL & INSTALLATION - F150 PICKUP - BI-FUEL -
GASOLINE/LPG article. If fuel tank(s) are being serviced, have fuel evacuated by trained personnel at a local
propane fuel station. LPG fuel vaporizes at normal barometric pressure at temperatures above -44°F (-42°C),
and expands to 270 times its volume as a liquid. Unnecessary venting of LPG fuel can create fire and health
hazards which could cause personal injury or death. Be alert for situations that may cause LPG fuel system to
vent fuel. These include extremely hot days, parking near a space heater, or hoisting a vehicle up near a ceiling
heater. Release of LPG fuel in a confined area through pressure relief valve could occur. Release of LPG fuel in
a confined area could result in an accumulation of flammable vapors. If fuel is vented near a heat source, a fire
or explosion could occur.
DO NOT use paint drying ovens for LPG fueled vehicles. Heat from paint drying ovens will increase pressure
in fuel tanks and could cause venting of LPG fuel vapor into oven and result in a fire from heat or sparks in
electrical equipment. If fuel is confined inside an oven, an explosion may occur. If a confined area, such as a
lubrication pit, has been subjected to LPG gas, the area should be inspected for adequate oxygen levels by a
local health department before being entered, or personal injury or death may occur. LPG fuel system pressure
must be relieved before any component can be removed. Fuel tanks must be evacuated prior to tank removal.
Removal of components without pressure relief or tank evacuation can cause LPG fuel to escape and cause
injury or death.
Inertia Fuel Shutoff Switch Reset Procedure
Turn ignition off. Check for fuel leaks in engine compartment. If no leak is present, reset IFS switch by pushing
reset button on top of switch. Turn ignition switch to ON or START position for a few seconds, then to OFF
position again. Again, check for leaking fuel.
NOTE:
Fuel system is designed to vent excess fuel vapor pressure in high ambient
temperatures, such as those experienced in desert locations. Pressure relief
valve will vent fuel and automatically reset itself. Observe all warnings when
performing LPG leak test. See LEAK TEST - ALL BI-FUEL VEHICLES under
FUEL SYSTEMS.
WARNING:
If you see or smell gasoline at any time other than during fueling, DO NOT
reset Inertia Fuel Shutoff (IFS) switch.
NOTE:
With IFS in CLOSED position, reset button can be depressed an additional 1/16"
against the spring.
2003 Ford Pickup F150
2003 ENGINE PERFORMANCE System & Component Testing - Bi-Fuel - Gasoline/LPG