Mercury MerCruiser MCM 454 Mag MPI Service Manual page 573

FUEL INJECTION SYSTEM TROUBLESHOOTING
Lack of Power, Sluggish or Spongy Symptom (Continued)
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Index
Page 5D-14
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1. Check for proper fuel pressure while
the condition exists.
Refer to Table A-4 in "General Sys-
tem Diagnostics" section.
2. If a problem is found, repair as
necessary.
Was a problem found?
1. Check for injector driver CKT's 467
or 468 for an open.
2. If a problem is found, repair as
necessary.
Was a problem found?
1. Check for proper operation of
Ignition Control (IC) circuit nd the
Knock Sensor (KS) circuit.
2. If a problem is found, repair as
necessary.
Was a problem found?
1. Check for proper ignition voltage
output.
Refer to Table A-7 in "General Sys-
tem Diagnostics" section.
2. If a problem is found, repair as
necessary.
Was a problem found?
1. Remove spark plugs, check for wet
plugs, cracks, wear, improper gap,
burned electrodes
deposits.
Refer to "Distributor Ignition Sys-
tem" in "Description and System Op-
eration" section.
NOTE: If park plugs are gas or oil fouled,
the cause of the fouling must be deter-
mined before replacing the spark plugs.
2. If a problem is found, repair as
necessary.
Was a problem found?
1. Check ignition coil for cracks or
carbon tracking.
2. If a problem is found, repair as
necessary.
Was a problem found?
-
-
-
-
or heavy
-
-
SERVICE MANUAL NUMBER 23
Go to OBD
System
Go to Step 7
Check
Go to OBD
System
Go to Step 8
Check
Go to OBD
System
Go to Step 9
Check
Go to OBD
System
Go to Step 10
Check
Go to OBD
System
Go to Step 11
Check
Go to OBD
System
Go to Step 12
Check
90-861326--1 MARCH 1999