Mazda 626 Station Wagon, Руководство по ремонту

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TROUBLESHOOTING
STEP INSPECTION RESULTS ACTION
4 Connect NGS tester to DLC.
Access RPM PID, MAF V PID, TP V PID, and
VS PID.
Except for GF4A-EL models
• RPM PID
• MAF V PID
• TP V PID
• VS PID
For GF4A-EL models
• RPM PID
• MAF PID
• TP V PID
• VSS PID
Drive vehicle while monitoring PIDs.
Are PIDs within specifications?
(See F1-25 PCM INSPECTION (except for
GF4A-EL models))
(See Section F (for GF4A-EL models))
Yes Go to next step.
No RPM PID:
Inspect CKP sensor and related harness for
vibration and/or intermittent open/short circuit.
MAF V (MAF) PID:
Inspect for intermittent open circuit of MAF sensor
and related wiring harness.
TP V PID:
Inspect if TP sensor output increases smoothly.
VS (VSS) PID:
Inspect for intermittent open circuit of VSS and
related wire harness.
5 Visually inspect CKP sensor and teeth of
crankshaft pulley.
Are CKP sensor and teeth of crankshaft pulley
okay?
Yes Go to next step.
No Replace malfunctioning parts.
6 Measure gap between CKP sensor and teeth of
crankshaft pulley.
Specification
0.5— 1.5 mm {0.020—0.059 in}
Is the gap within specification?
Yes
Go to next step.
No Adjust CKP sensor.
7
Inspect spark plug conditions.
Is spark plug wet, covered with carbon or
grayish white?
Yes Spark plug is wet or covered with carbon:
Inspect for fuel leakage from fuel injector.
Spark plug Is grayish white:
Inspect for clogged fuel injector.
No Install spark plugs on original cylinders.
Go to next step.
8 Remove and shake PCV valve.
Does PCV valve rattle? Yes Go to next step.
No Replace PCV valve.
9 Is there restriction in exhaust system? Yes Inspect exhaust system.
No Go to next step.
10 Install fuel pressure gauge between fuel main
pipe and fuel distributor.
Connect jumper wire between F/P terminal at
DLC in engine compartment and GND.
Turn ignition switch on.
Is fuel line pressure correct with ignition switch
on?
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.
High:
Inspect pressure regulator for high pressure
cause.
Inspect for clogged fuel return line.
11 Install vacuum gauge to intake manifold.
Start engine.
Does fuel pressure gauge reading increase as
vacuum gauge reading decreases and/or does
fuel pressure gauge reading decrease as
vacuum reading increases?
Yes Go to next step.
No
Connect vacuum pump to pressure regulator.
Start engine. Verify that fuel pressure gauge
reading changes as vacuum changes.
If changes, inspect vacuum line.
If does not change, replace pressure regulator.
F1-126