Mazda MX-6 1998, Руководство по ремонту

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TROUBLESHOOTING [ENGINE CONTROL FS]
DTC P0171
P0172
P1130
P1131
P1132
Adaptive fuel control system too lean
Adaptive fuel control system to rich
Lack of heated oxygen sensor (Front) (H 0 2 S 11) switch adaptive fuel at limit
Lack of heated oxygen sensor (Front) (H 02S 11) switch sensor indicates too lean
Lack of heated oxygen sensor (Front) (H 02S 11) switch sensor indicates too rich
DESCRIPTION
• DTC P0171 indicates fuel/air ratio is too lean. Fuel trim system is at rich correction limit.
• DTC P0172 indicates fuel/air ratio is too rich. Fuel trim system is at lean correction limit.
• DTC P1130 indicates fuel control system has reached maximum compensation for lean or
rich condition and heated oxygen sensor is not switching.
• DTC P1131 indicates fuel/air ratio is correcting rich for an overly lean condition. Heated
oxygen sensor voltage is less than 0.45 volt.
• DTC P1132 indicates fuel/air ratio is correcting lean for an overly rich condition. Heated
oxygen sensor voltage is greater than 0.45 volt.
[Possible Cause]
Fuel System Induction System
• Excessive fuel pressure • Air leaks after the MAF sensor
• Leaking fuel injector(s) • Vacuum leaks
• Leaking pressure regulator • Restricted air inlet
• Low fuel pressure or running out of fuel • Positive crankcase ventilation (PCV) system
• Contaminated fuel injector(s) • Fuel purge system
• Improperly seated engine oil dipstick
Base Engine
• Oil overfill
EGR System
• Cam timing • Leaking gasket
• Cylinder compression • Stuck open EGR valve
• Exhaust leaks before or near heated oxygen sensor • Leaking diaphragm
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.
c r 0 1 -1 4 BEFORE REPAIR PROCEDURE
c r 0 1 -1 4 AFTER REPAIR PROCEDURE
STEP INSPECTION ACTION
1 VISUAL CHECKS
• Check intake air system for leaks,
obstructions and damage.
• Check air cleaner element and air cleaner
housing for blockage.
• Verify integrity of PCV system.
• Check for vacuum leaks.
• Are any of the above concerns present?
Yes
SERVICE as necessary.
RESET PCM to completely clear DTCs.
kt
After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
No Go to next step.
2 PERFORM KOER SELF-TEST
• Key off.
• NGS tester connected.
• Disconnect fuel vapor hose from intake
manifold and plug fitting at intake manifold.
• Start engine and run at 2,000 rpm for 5
minutes and return to idle.
• Perform KOER self-test.
•
Are any heated oxygen sensor DTCs
P1127, P1131
or
P1132
present?
Yes
If DTC(s) P1127 is present:
Go to DTC(s) charts PROCEED as required.
DTCs P1131 or P1130:
Go to next step.
DTCs P1132 o r P1130:
Go to step 9.
No For Continuous DTCs P1130, P0171, and P0172 Only:
Go to step 12.
If DTC(s) P1132 is no longer present:
RECONNECT fuel vapor line.
Check purge solenoid valve DTC (P0443).
All others:
Fault that produced DTC is intermittent.
Check for poor connection or component malfunction
(SERVICE or REPLACE as necessary).
Go to ENGINE SYMPTOM TROUBLESHOOTING No. 27
0 1 -0 1 A -3 4