Transcript FUEL INJECTION SYSTEM OPERATION CBC AUTO

FUEL INJECTION
SYSTEM OPERATION
CBC
AUTO
FUEL INJECTION TYPES
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THROTTLE BODY INJECTION (TBI)
– INJECTED ABOVE THROTTLE PLATES
– SINGLE INJECTOR
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CENTRAL PORT INJECTION (CFI)
– INJECTED ABOVE THROTTLE PLATES
– USUALLY MORE THAN ONE
INJECTOR
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PORT FUEL INJECTION (PFI)
– INJECTORS IN INTAKE RUNNERS
CBC
AUTO
TBI UNIT
(SOMETIMES CALLED CFI)
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FIRST STEP FROM
CARBURETORS
SOME CARB
CHARACTERISTICS
LOW PRESSURE
MOVEABLE PINTLE
PRESSURE IS
REGULATED
SERVICEABLE
FIG 6-40 CLASS
CBC
AUTO
LOW PRESSURE SYSTEM
CBC
AUTO
FUEL INLET AND OUTLET
CBC
AUTO
LOW PRESSURE FUEL
INJECTOR
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13-16 PSI
TWO O-RINGS
BALL PINTLE
USED ON TBI
AND CFI
SYSTEMS
MESH SCREEN
EASY TO
REPLACE
CBC
AUTO
TWO INJECTOR SYSTEM
CBC
AUTO
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PORT FUEL
INJECTION
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INJECTS AT
EACH CYLINDER
HIGHER
PRESSURE
FED OFF OF FUEL
RAIL
MORE EFFICIENT
OPERATION
MODES
– MULTI-PORT
– SEQUENTIAL
CBC
AUTO
PORT FUEL INJECTION
CBC
AUTO
CENTRAL POINT
INJECTION
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GM SYSTEM
INJECTOR
LOCATED IN
LOWER HALF OF
INTAKE
MANIFOLD
POPPET VALVES
HIGH PRESSURE
60 PSI
CBC
AUTO
CONTINUOUS
INJECTION
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SPRAYS ALL THE TIME
MIXTURE CONTROL UNIT
FUEL DISTRIBUTOR
CONTROL PRESSURE REGULATOR
CBC
AUTO
FUEL PRESSURE
REGULATOR
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Used on TBI
systems
Provides constant
fuel supply
Fuel pressure on
one side
Fuel pressure opens
regulator under a
certain pressure.
Spring is calibrated
CBC
AUTO
INJECTION SYSTEM
SERVICE
CBC
AUTO
SYSTEM CHECKS
ADEQUATE AIR SUPPLY
 PRESSURIZED FUEL SUPPLY
 ADEQUATE TRIGGER SIGNAL
 NO VACUUM LEAKS
 GOOD IGNITION SYSTEM
 GOOD ENGINE MECHANICAL
 GOOD FUEL QUALITY
 PCM OPERATION
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CBC
AUTO
FUEL DELIVERY
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Fuel Pump noises
Does fuel pump
run at all?
Fuel filter
condition?
Connections to fuel
pump
CBC
AUTO
COMPONENT CHECKS
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AIR INDUCTION
AIR FLOW SENSORS
THROTTLE BODY
FUEL SYSTEM
CHECKS
FUEL DELIVERY
INJECTOR CHECKS
INJECTOR
CLEANING
6-61 LAB
CBC
AUTO
INERTIA SWITCH
CBC
AUTO
INJECTOR TESTS
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ELECTRICAL OPERATION
– VOLTAGE SIGNALS
– SCOPE TESTING
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MECHANICIAL OPERATION
– PINTLE OPERATION
– BALANCE TEST
– FLOW
CBC
AUTO