Mazda MX-6 1998, Руководство по ремонту, Страница: 249 / 1282

TROUBLESHOOTING [ENGINE CONTROL KL]
STEP
INSPECTION ACTION
25
CHECK FUEL PRESSURE, ENGINE
RUNNING
• Key off.
• Install fuel pressure tester.
• Disconnect vacuum hose at fuel pressure
regulator and plug It.
• Drive vehicle with heavy accelerations
while observing fuel pressure gauge
reading.
• Does fuel pressure reading hold steady
within 21 kPa {0.21 kgf/cm2, 3 psi}
during test?
Yes UNPLUG vacuum hose and RECONNECT to fuel
pressure regulator.
Go to next step.
No Go to step 29.
26 CHECK FUEL PRESSURE REGULATOR
RESPONSE TO VACUUM
• Key off.
• Install fuel pressure tester.
• Install vacuum gauge to intake manifold.
• Start engine and observe both gauges.
• Accelerate and decelerate engine speed to
vary vacuum gauge reading.
• Does fuel pressure gauge reading
increase as vacuum gauge reading
decreases, or decrease as vacuum
gauge reading increases?
Yes REMOVE vacuum gauge and fuel pressure tester.
Concern is elsewhere.
tr ENGINE SYMPTOM TROUBLESHOOTING for
further direction.
No Go to next step.
27 CHECK VACUUM SUPPLY
• Key off.
• Install fuel pressure tester.
• Disconnect vacuum hose at fuel pressure
regulator and plug it.
• Install hand held vacuum pump to fuel
pressure regulator.
• Start engine and let run at idle.
• Observe fuel pressure while applying
vacuum.
• Does fuel pressure change as vacuum
changes?
Yes SERVICE vacuum system.
UNPLUG vacuum hose and RECONNECT to pressure
regulator.
RECHECK fuel pressure.
No REPLACE fuel pressure regulator.
RECHECK fuel pressure.
28
CHECK FUEL INJECTOR LEAKAGE AND
FLOW
• Verify that flow rate for each fuel injector is
within specification using SST (49 E018
9 AO).
• Is flow rate for each injector within
specification?
Yes
VERIFY for other leaks.
If none are found,
REPLACE fuel pump module.
RECHECK fuel pressure.
No REPLACE damaged fuel injector.
RECONNECT all components.
RECHECK fuel pressure.
29
CHECK VOLTAGE AT FUEL PUMP VEHICLE
HARNESS CONNECTOR
• Key off.
• Disconnect fuel pump harness connector at
fuel pump. Inspect for damaged or pushed
out pins, corrosion and loose wires. Service
as necessary.
• Key on, engine off.
• Connect digital multimeter between fuel
pump power circuit and fuel pump ground
circuit at fuel pump vehicle harness
connector.
• Enter Output Test Mode and active pump
circuit. Record reading.
• Is voltage greater than 10.5 volts?
Yes EXIT Output Test Mode.
RECONNECT fuel pump harness connector.
Go to next step.
No CHECK ground and power circuit.
SERVICE as necessary.
RECHECK fuel pressure.
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