Mazda MX-6 1998, Workshop Manual

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TROUBLESHOOTING [ENGINE CONTROL KL]
STEP
INSPECTION
ACTION
29
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.
30
Check engine condition while tapping EGR
valve housing. Does engine condition
improve?
Yes Replace EGR valve.
No
Go to next step.
31 Is engine compression correct?
Yes Check for valve timing.
No Check for cause.
32 Verify test results. If okay, return to diagnostic index to service any additional symptoms.
5 CRANKS NORMALLY BUT WILL NOT START
DESCRIPTION
• Starter cranks engine at normal speed but engine will not run
• Refer to “ENGINE STALLS” if this symptom appears after engine stall
• Fuel in tank
• Battery in normal condition
POSSIBLE
CAUSE
• Operation of immobilizer system
• Air leak from intake air system
• Improper operation of IAC valve
• No signal from crankshaft position sensor due to sensor, related wire or incorrect installation
• Spark leak from hightension leads
• PCV valve malfunction
• Restriction in exhaust system
• Open or short circuit in fuel pump and related harness
• Fuel pump mechanical malfunction
• Fuel injector clogged
• No battery power supply to PCM
• Open PCM ground or vehicle body ground
• EGR valve malfunction
• Low engine compression
• Vacuum leak
• Poor fuel quality
• Air cleaner restriction
• Disconnect electrical connector disconnection
• Inadequate fuel pressure
• Fuel leak from injector
• Purge solenoid valve malfunction
STEP INSPECTION
ACTION
1
Note
• Following test should be performed test
vehicles equipped with immobilizer system.
Skip this test and go to step 12 for
non-immobilizer system.
Is
following condition appeared?
• Engine is not completely started and DTC
P1624 is retreived.
Yes Go to step 3.
No Go to next step.
2 Is engine stalled after approx. 2 seconds
since engine is started?
Yes
Go to next step.
No Immobilizer system is okay.
3 Is immobilizer unit connector securely
connected to immobilizer unit?
Yes Go to next step.
No Connect immobilizer unit connector securely.
Return step 2.
4
Does immobilizer indicator light flash and
indicate following immobilizer DTCs?
DTC: 01, 02, 03, 11,21
Yes
Go to “ON BOARD DIAGNOSTIC FUNCTION” of
immobilizer system.
No Go to next step.
5 Does immobilizer indicator light illuminate? Yes Go to step 8.
No Go to next step.
6 Does indicator light flush and indicate
following immobilizer system DTC after more
than 135 seconds after ignition switch turned
ON?
DTC: 24, 30
Yes Go to “ON BOARD DIAGNOSTIC FUNCTION” of
immobilizer system.
No Go to next step.
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