Mazda MX-6 1998, Workshop Manual

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TROUBLESHOOTING [ENGINE CONTROL FS]
3 Wet/carbon stuck on all plugs
[TROUBLESHOOTING HINTS]
CD Spark-Spark weak
© Air/fuel mixture-Too rich
® Compression-Low compression
Others
© Clogs in intake/exhaust system
Warning
Following troubleshooting flow chart contains fuel system diagnosis and repair procedures. Read following
warnings before performing fuel system service:
• Fuel vapor is hazardous. It can easily ignite, causing serious injury and damage. Always keep sparks and flames
away from fuel.
• Fuel line spills and leaks are dangerous. Fuel can ignite and cause serious injuries or death and damage. Fuel
can also irritate skin and eyes. To prevent this, always complete “BEFORE REPAIR PROCEDURE” and “AFTER
REPAIR PROCEDURE” described in this manual.
tr 0 1 -1 4 BEFORE REPAIR PROCEDURE
e r 0 1 -1 4 AFTER REPAIR PROCEDURE
STEP
INSPECTION ACTION
1 Is air cleaner element tree of restrictions?
Yes Go to next step.
No Replace air cleaner element.
2
Carry out spark test.
Is a strong blue spark visible at each cylinder?
Yes Go to next step.
No Repair or replace.
3 Carry out fuel pressure inspection.
Is fuel pressure correct?
Fuel line pressure
260— 310 kPa {2.6— 3.2 kgf/cm2,
37— 46 psi} at ignition switch ON
Yes Go to next step.
No Repair or replace.
4 Check following PID.
• MAF PID.
c? 01—40A MASS AIR FLOW SENSOR
INSPECTION [FS]
• ECT PID.
a- 0 1 -4 0 A ENGINE COOLANT
TEMPERATURE SENSOR
INSPECTION [FS]
• H02S11, H 02S12, H02S21, H02S22
C r 01—40A HEATED OXYGEN SENSOR
INSPECTION [FS]
(When engine can be started).
Are terminals okay?
Yes Go to next step.
No Repair or replace.
5 Carry out purge control inspection (When
engine can be started).
Is purge control correct?
Yes Go to next step.
No Repair or replace.
6 Carry out compression inspection.
Is compression correct?
Yes Check clogs in exhaust system.
No Repair or replace.
01-01A -1 71