Mazda MX-6 1998, Workshop Manual

Page: 271 / 1282

TROUBLESHOOTING [ENGINE CONTROL KL]
DTC P0442 Evaporative emission control system leak detected (Small leak)
DESCRIPTION
• DTC P0442 indicates that leak has been detected [as small as 1 mm (0.040 inch)] in
Evaporative Emission System.
[Possible Cause]
• Purge solenoid valve malfunction • Barometric absolute pressure sensor malfunction
• Canister Drain Cut Valve (CDCV) malfunction • Fuel tank level sensor malfunction
• Loose fuel filler cup • Fuel tank pressure sensor malfunction
• Charcoal canister malfunction • Engine coolant temperature sensor malfunction
• Catch tank malfunction • Intake air temperature sensor malfunction
• Pressure control valve malfunction • Throttle position sensor malfunction
• Cracked fuel tank • Mass air flow sensor malfunction
• Fuel tank component parts poorly installed • Vehicle speed sensor malfunction
• Evaporative hose damaged or loose • Poor connection of connector
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
kt 0 1 -1 4 AFTER REPAIR PROCEDURE
STEP INSPECTION
ACTION
1
CHECK FOR OTHER CONTINUOUS
MEMORY DTC
Check for other Continuous Memory DTCs
which could cause Evaporative Emission
Monitor DTC.
• Key off.
• NGS tester connected.
• Key on, engine off.
• Retrieve and record any Continuous
Memory DTCs.
• Are there any other continuous Memory
DTCs present?
Yes Go to appropriate DTC test.
DISREGARD Evaporative Emission Monitor DTC at this
time.
No
Go to next step.
2 CHECK FOR KEY ON ENGINE OFF (KOEO)
SELF TEST
• Activate key on, engine off (KOEO) self
test.
• Are any KOEO DTCs displayed?
Yes Go to appropriate DTC test.
No Go to next step.
3 CHECK FOR KEY ON ENGINE RUNNING
(KOER) SELF TEST
• Key on, engine running.
• Warm up engine to normal operating
temperature.
• Activate key on, engine running (KOER)
self test.
• Are any KOER DTCs displayed?
Yes Go to appropriate DTC test.
No Go to next step.
4 INSPECTION OF FUEL FILLER CAP
• Key off.
• Disconnect NGS tester.
• Confirm filler cap is not either
disconnected, loose or damaged.
Note
• When filler caps other than order entry
system (OES) caps are attached, it is
considered abnormal.
• Is fault detected?
Yes REPLACE or PROPERLY attach filler cap.
RESET PCM to completely clear DTCs.
vr
After Repair Procedure
COMPLETE OBD II Drive Mode.
RERUN OBD Test.
No Go to next step.
01-01B-65