Mazda 626 Station Wagon, Руководство по ремонту

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TROUBLESHOOTING
STEP
INSPECTION
RESULTS ACTION
25 Install fuel pressure gauge between fuel main
pipe and fuel distributor.
Connect jumper wire between F
IP terminal at
DLC in engine compartment and GND.
Turn ignition switch on.
Is fuel line pressure correct when ignition switch
is cycled on/off five times?
Fuel line pressure
210—260 kPa {2.1—2.6 kgf/cm2, 30—36 psi}
Yes Go to next step.
No Zero or low:
Inspect fuel pump unit circuit.
Inspect for open fuel pump body relief valve.
Inspect for fuel leakage inside pressure
regulator.
Inspect for clogged main fuel line.
Inspect PRC solenoid, related vacuum hose,
and harnesses.
High :
Inspect pressure regulator for high pressure
cause.
Inspect for clogged fuel return line.
26 Visually inspect for fuel leakage at fuel injector
O-ring and fuel line. Service as necessary.
Is fuel line pressure held after ignition switch is
turned off?
Fuel line pressure
More than 150 kPa {1.5 kgf/cm2, 21 psi} for 5
min.
Yes Go to next step.
No Inspect pressure regulator diaphragm condition.
If condition is okay, inspect fuel injector.
If condition is not okay, replace pressure
regulator.
27 Disconnect vacuum hose between purge
solenoid valve and intake manifold from purge
solenoid valve side.
Plug opening end of vacuum hose.
Attempt to start engine.
Is starting condition improved?
Yes Inspect if purge solenoid valve is stuck open
mechanically.
Inspect evaporative emission control system.
No Go to next step.
28 Is air leakage felt or heard at intake-air system
components while racing engine to higher
speed?
Yes Repair or replace.
No Go to next step.
29 Inspect engine condition while tapping EGR
valve housing.
Does engine condition improve?
Yes Replace EGR valve.
No Go to next step.
30
Is engine compression correct?
Yes
Inspect valve timing.
No Inspect for causes.
31
Verify test results. If okay, return to diagnostic index to service any additional symptoms.
NO .6 SLO W RETURN TO IDLE
6 Slow return to idle
DESCRIPTION • Engine takes more time than normal to return to idle speed.
• ECT sensor malfunction
POSSIBLE
• Thermostat is stuck open.
CAUSE • Throttle body malfunction
• Air leakage from intake-air system
Diagnostic Procedure
STEP
INSPECTION RESULTS
ACTION
1 Connect NGS tester to DLC.
Turn ignition switch on.
Retrieve any DTC.
Is any DTC displayed?
Yes DTC Is displayed:
Go to appropriate DTC test.
No
No DTC is displayed:
Go to next step.
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