Suzuki GSF1250 Service Manual page 78

1A-9 Engine General Information and Diagnosis:
Condition
Engine noisy (Noise
seems to come from
water pump)
Engine runs poorly in
high speed range
(Defective engine internal/
electrical parts)
Engine runs poorly in
high speed range
(Defective air flow
system)
Engine runs poorly in
high speed range
(Defective control circuit
or sensor)
Engine lacks power
(Defective engine internal/
electrical parts)
Possible cause
Worn or damaged impeller shaft.
Worn or damaged mechanical seal.
Contact between pump case and
impeller.
Too much play on pump shaft bearing.
Weakened valve springs.
Worn camshafts.
Valve timing out of adjustment.
Too narrow spark plug gap.
Ignition not advanced sufficiently due to
poorly working timing advance circuit.
Defective ignition coil/plug gap.
Defective CKP sensor.
Defective ECM.
Clogged air cleaner element.
Clogged fuel hose, resulting in
inadequate fuel supply to injector.
Defective fuel pump.
Defective TP sensor.
Defective STP sensor or STVA.
Clogged air cleaner element.
Defective throttle valves.
Defective ISC valve.
Sucking air from throttle body joint.
Defective ECM.
Imbalancing throttle valve
synchronization.
Defective STP sensor or STVA.
Low fuel pressure.
Defective TP sensor.
Defective IAT sensors.
Defective IAP sensor.
Defective ECM.
TP sensor out of adjustment.
Defective STP sensor or STVA.
Defective GP sensor.
Defective CKP sensor.
Loss of tappet clearance.
Weakened valve springs.
Valve timing out of adjustment.
Worn piston rings or cylinders.
Poor seating of valves.
Fouled spark plugs.
Incorrect spark plugs.
Clogged fuel injectors.
Defective TP sensor.
Clogged air cleaner element.
Sucking air from throttle valve or
vacuum hose.
Too much engine oil.
Defective fuel pump or ECM.
Defective CKP sensor and ignition coil/
plug caps.
Imbalancing throttle valve
synchronization.
Defective STP sensor or STVA.
Correction / Reference Item
Replace.
Replace.
Replace.
Replace.
Replace.
Replace.
Adjust.
Adjust.
Replace ECM.
Replace.
Replace.
Replace.
Clean.
Clean and prime.
Replace.
Replace.
Replace.
Clean or replace.
Adjust or replace.
Replace.
Repair or replace.
Replace.
Adjust.
Replace.
Repair or replace.
Replace.
Replace.
Replace.
Replace.
Adjust.
Replace.
Replace.
Replace.
Adjust.
Replace.
Adjust.
Replace.
Repair.
Clean or replace.
Adjust or replace.
Replace.
Replace.
Clean.
Retighten or replace.
Drain out excess oil.
Replace.
Replace.
Adjust.
Replace.