MerCruiser 305 CID (5.0L), Руководство по обслуживанию

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FUEL INJECTION SYSTEM TROUBLESHOOTING
SERVICE MANUAL NUMBER 24
90-861327--1 OCTOBER 1999 Page 5F-9
Lack of Power, Sluggish or Spongy Symptom
Step Action Yes No
PROCEED TO
Definition: Engine delivers less than expected power. Little or no increase in speed when
throttle lever is advanced part way.
1
Was the “On-Board Diagnostic” (OBD)
System Check performed?
Step 2 OBD
2
If possible, compare engine performance with
a similar engine.
Is engine performance close to similar
engine?
No problem
found
Step 3
3 Was visual / physical check performed?
Step 4
Visual/ Physical
Check
4
1. Remove and check flame arrestor for dirt,
or for being restricted.
2. Clean or replace flame arrestor.
Was flame arrestor dirty or restricted? Step 5
5
1. Check for contaminated fuel.
2. Check water separating fuel filter.
Was a problem found?
Step 6
6
1. Check for proper fuel pressure while the
condition exists.
•
Refer to Table A-4 in “General System
Diagnostics” section.
Was fuel pressure 30 psi for EFI or 3–7 psi
for carbureted engines?
Step 7
7
1. Check for injector driver CKT 467 or CKT
468 for an open.
Did you find an open? Step 8
8
1. Check for proper operation of Ignition Con-
trol (IC) circuit and the Knock Sensor (KS)
circuit.
Was a problem found?
Step 9
9
1. Check for proper ignition voltage output.
•
Refer to Table A-7 in “General System
Diagnostics” section.
Was a problem found?
Step 10
10
1. Remove spark plugs, check for wet plugs,
cracks, wear, improper gap, burned elec-
trodes or heavy deposits.
•
Refer to “Distributor Ignition System” in
“Description and System Operation” sec-
tion.
NOTE: If park plugs are gas or oil fouled, the
cause of the fouling must be determined before
replacing the spark plugs.
Were spark plugs damaged? OBD
Step 11
Index