
TROUBLESHOOTING [ENGINE CONTROL KL]
DTC
P0420
Catalyst efficiency below threshold
DESCRIPTION
• DTCs P0420 indicate catalyst system efficiency is below acceptable threshold
[Possible Cause]
• Use of leaded fuel
• Fuel pressure to high
• Oil contamination
• Damaged exhaust system pipe
• Cylinder misfiring
• Damaged exhaust manifold
• Damaged heated oxygen sensor
• Damaged silencer/tail-pipe component
• Damaged ECT sensor
• Damaged catalytic converter
• Downstream heated oxygen sensor wires improperly
connected
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
rr
0 1 -1 4 AFTER REPAIR PROCEDURE
STEP
INSPECTION
ACTION
1
CHECK FOR MISFIRE MONITOR DTC
Note
• Complete spark timing check in OBD Test
before proceeding with this step. Spark
timing retarded below specification may
increase exhaust gas temperature and
decrease catalyst efficiency overtime.
o ■ 0 1 -1 7 IGNITION SYSTEM
INSPECTION
Note
Be sure customer has not:
• Refueled vehicle with leaded gasoline.
• Experienced excessive oil consumption.
Note
• Internal deterioration of catalytic converter
is usually caused by abnormal engine
operation upstream of catalyst. Events that
may produce higher than normal
temperature in catalyst are particularly
suspect. For example, misfiring can cause
higher than normal catalyst operating
temperature higher than normal.
• Key on, engine off.
• Retrieve and record all Continuous Memory
DTCs.
•
Were any of following misfire monitor
DTCs recorded: P0300, P0301, P0302,
P0303, P0304, P0305 and P0306?
Yes
Go to pinpoint test for misfire DTCs.
No
Go to next step.
0 1 -0 1 B -6 0
Содержание MX-6 1998
Страница 1: ......
Страница 501: ...STARTING SYSTEM 3 If not as specified replace the starter interlock switch 01 19 3...
Страница 803: ...MANUAL TRANSAXLE W 6 U 5 1 5 W A C 05 15 7...
Страница 934: ...CONTROL SYSTEM CONTROL SYSTEM STRUCTURAL VIEW W6U740WA0 07 40 2...
Страница 983: ...SERVICE TOOLS 08 60 SERVICE TOOLS 08 RESTRAINTS S S T 08 60 1 08 RESTRAINTS SST 08 60 1...
Страница 1005: ...TROUBLESHOOTING POWER DOOR LOCK SYSTEM From previous page Go to next page W 6 U 9 0 1 W H 3 09 01E 7...
Страница 1168: ...SEATS 4A 4 If not as specified replace the power seat switch 2A 2B t 4B 3A 1C 1A 1F W6U913WA9 09 13 7...