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by Jem270
Hey Al I don't remember, how far back do inertia switches go in Fords? It really is an easy way to leak down the fuel rails and as of yet I haven't had to bleed the schrader valve to remove any trapped air in the fuel rails. >yo,
start it, trip the Inertia Fuel Cut-Off Switch, wait until it dies, turn key off, begin work, complete work, RESET INERTIA SWITCH, start truck. If its not startable, put on saftey glasses and depress schrader valve
Turn it off pry the slot under the red button (later years) with a small screwdriver to pop it up - press it in when done
Source: by miesk5 at Ford Bronco Zone Forums
Inertia Fuel Cut-Off Switch Location pic in an 88
by Jem270
firewall, forward of the parking brake & clutch pedals
View attachment 11870
The IFS switch is used in conjunction with an electric fuel pump(s). The purpose of the IFS switch is to shut off the fuel pump in the event of an accident. It consists of a steel ball held in place by a magnet. When a sharp impact occurs, the ball breaks loose from the magnet, rolls up a conical ramp and strikes a target plate which opens the electrical contacts of the switch and shuts off the electric fuel pump. Once the switch is open, then it must be manually reset before restarting the vehicle.
This is the Ford version; btw all Upper Case is by Ford
WARNING: FUEL IN THE FUEL SYSTEM REMAINS UNDER HIGH PRESSURE EVEN WHEN THE ENGINE IS NOT RUNNING. TO AVOID INJURY OR FIRE, RELEASE THE FUEL PRESSURE FROM THE FUEL SYSTEM BEFORE DISCONNECTING ANY FUEL LINE. TO RELEASE THE PRESSURE FROM THE SYSTEM PERFORM THE FOLLOWING:
CONNECT THE ROTUNDA FUEL PRESSURE TESTING KIT 014-00447 OR EQUIVALENT AT THE SCHRADER VALVE LOCATED ON THE FUEL RAIL WITH THE TESTING KIT VALVE CLOSED.
GRADUALLY OPEN THE TESTING KIT VALVE TO RELIEVE FUEL PRESSURE IN THE VEHICLE FUEL SYSTEM AND DRAIN THE FUEL INTO A SUITABLE CONTAINER OR RETURN IT TO THE FUEL TANK.
TO AVOID UNNECESSARY FUEL SPILLAGE AND FIRE HAZARD AT ANY TIME FUEL LINES ARE DISCONNECTED, THE IGNITION SWITCH SHOULD BE IN THE OFF POSITION UNLESS FUEL PUMP OPERATION IS REQUIRED FOR TEST PURPOSES.
Reset Instructions
Turn ignition to OFF.
Check for leaking fuel in the engine compartment, fuel lines and tank(s).
If no fuel leak is apparent, reset the IFS switch by pushing the reset button on the top of the switch (refer to Owner Guide).
View attachment 11870
Note in the closed position the button can be depressed on additional 1/16 inch against a spring.
Turn ignition switch to START for a few seconds, then to OFF.
Again, check for leaking fuel.
WARNING: IF YOU SEE OR SMELL GASOLINE AT ANY TIME OTHER THAN REFUELING, DO NOT RESET THE IFS SWITCH.
-Kevin-
