Engine Operates Poorly At Idle - Mercury MerCruiser D2.8L D-Tronic Service Manual

TROUBLESHOOTING

Engine Operates Poorly at Idle

1. Clogged air cleaner
2. Plugged fuel suction line or filter
3. Air leaks: suction side fuel line, water
4. Water in fuel
5. Low grade or stale fuel
6. Fuel waxing or frozen water separating
7. Valve timing
8. Restricted or plugged exhaust
9. Injectors not functioning properly
10. Injection pump timing incorrect
11. Low compression
12. Water leaking into cylinders
13. Loose or broken engine mounts
14. Refer to SECTION 5 for complete
Page 1C-12
Cause
separating fuel filter or loose intake
manifold
fuel filter (cold weather)
diagnostic procedures for EDI
SERVICE MANUAL NUMBER 22
Special Information
4. Refer to SECTIONS 1B and 5A
7. Cam slipped in drive gear
9. Refer to SECTION 5E for EDI
Diagnosis
10. Refer to SECTION 5E for EDI
Diagnosis
11. Also check for defective (blown) head
gasket
12. Defective head gasket, exhaust
manifold, cracked head or intercooler
90-860074--1 FEBRUARY 2002