Mazda 2002 6 Workshop Manual page 356

STEP
6 Carry out fuel line pressure inspection.
Is fuel line pressure correct?
7 Inspect spark plug for following.
• Heat range
• Air gap
Is spark plug okay?
8 Remove suspected fuel injector.
Inspect following:
• Resistance
(See F–31 FUEL INJECTOR
• Fuel injection volume
(See F–31 FUEL INJECTOR
Are all above items okay?
9 Is air cleaner element free of restrictions?
10 Carry out spark test.
Is strong blue spark visible at each cylinder?
11 Carry out fuel line pressure inspection.
Is fuel line pressure correct?
(See F–20 FUEL LINE PRESSURE
INSPECTION)
12 Inspect following PIDs.
• ECT
• O2S11 (When engine can be started)
• MAF
(See F–45 PCM
Are PIDs okay?
13 Carry out purge control inspection.
(When engine can be started)
(See F–233 Purge Control System
Is purge control correct?
14 Carry out compression inspection.
Is compression correct?
15 When engine cannot be started, inspect intake-
air system for air leakage.
When engine can be started, carry out intake
manifold vacuum inspection.
Is air sucked in from intake-air system?
16 Carry out fuel line pressure inspection.
Is fuel line pressure correct?
(See F–20 FUEL LINE PRESSURE
INSPECTION)
17 Verify test results.
• If okay, return to diagnostic index to service any additional symptoms.
• If malfunction remains, replace or reprogram PCM.
End Of Sie
F–226
TROUBLESHOOTING
INSPECTION
INSPECTION.)
INSPECTION.)
INSPECTION.)
Inspection.)
RESULTS
Yes Inspect fuel injector for following:
• Open or short in injector
• Leakage
• Injection volume
No Zero or low:
Inspect fuel pump circuit.
Inspect for fuel pump relief valve open.
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.
Yes Go to next step.
No Replace spark plug.
Yes Inspect for open circuit between suspected fuel injector
connector terminal and PCM connector following
terminals:
• For #1 or #4 cylinder: 1A
• For #2 or #3 cylinder: 1B
No Replace fuel injector.
Yes Go to next step.
No Replace air cleaner element.
Yes Go to next step.
No Repair or replace malfunctioning parts.
Yes Go to next step.
No Zero or low:
Inspect for clogged fuel line.
If okay, replace fuel pump unit.
High:
Replace fuel pump unit.
Yes Go to next step.
No Repair or replace malfunctioning parts.
Yes Go to next step.
No Repair or replace malfunctioning parts.
Yes Inspect for clogging in exhaust system.
No Repair or replace malfunctioning parts.
Yes Repair or replace malfunctioning part.
No Go to next step.
Yes Inspect following PIDs.
• ECT
• O2S11
• MAF
(See F–45 PCM
Inspect PCM GND condition.
No Zero or low:
Inspect for clogged fuel line.
If okay, replace fuel pump unit.
High:
Replace fuel pump unit.
ACTION
INSPECTION.)