Detonation
POSSIBLE CAUSE ACTIONWITH NO BOOST
Low grade fuel ^ Drain fuel tank and fill with
correct octane fuel
Incorrect valve timing and/or ^ Refer to ENGINE MECHANICAL
clearance for diagnostic procedures
Ignition timing advanced too far ^ Refer to IGNITION SYSTEMS/
ADJUSTMENT PROCEDURES
WITH NORMAL BOOST
Low grade fuel ^ Drain fuel tank and fill with
correct octane fuel
Ignition timing advanced too far ^ Refer to IGNITION SYSTEMS/
ADJUSTMENT PROCEDURES
Insufficient fuel supply ^ Restriction or low fuel pressure,
Refer to FUEL SYSTEMS/
ELECTRONIC FUEL INJECTION-EFI
EGO sensor malfunction ^ Refer to COMPUTERIZED ENGINE CONTROLS
Vane airflow meter malfunction ^ Refer to COMPUTERIZED ENGINE CONTROLS
Engine overheating ^ Service as required
Oil leaking into compressor ^ Refer to SYSTEM TESTS/LP11
from turbocharger TURBOCHARGER SEAL LEAKAGE TEST
Valve seals leaking oil ^ Service as required