Fuel Shut-Off Valves; Heated Exhaust Gas Oxygen (Hego) Sensor - Kohler KG2204 Service

1.9. Fuel Shut-Off Valves

Figure 1-10 Fuel Solenoid Valve
Figure 1-11 Dual-Solenoid Fuel Valve
Two solenoid valves or one dual-solenoid valve are
mounted upstream of the engine. The fuel solenoid
valves provide automatic fuel on/off control. The
engine starting battery powers the solenoid valve and
the engine starting controls open the valves when the
engine cranks or runs.
16 Fuel System Overview
1.10. Heated Exhaust Gas Oxygen
(HEGO) Sensor
Figure 1-12 HEGO Sensor
The heated exhaust gas oxygen (HEGO) sensor
mounts to the exhaust system and is composed of a
sensor and an internal heating element.
During operation, heat from the exhaust increases the
temperature of the heating element and activates the
sensor. Once activated, the sensor measures the
oxygen content in the exhaust gas and sends a signal
to the ECM.
The ECM uses this signal to adjust the fuel flow to the
engine and to prevent the fuel flow from becoming too
rich or too lean. If the sensor signal indicates that the
fuel is too rich or too lean for an extended period of
time, the ECM will log a diagnostic code.
Important: Silicone sprays or inappropriate RTV
(room temperature
contaminate the HEGO sensor. Contaminated HEGO
sensors can produce false or high readings resulting in
poor fuel mixtures and severe performance problems.
Always verify that the sealer is safe to use with the
HEGO sensor before applying the sealer.
vulcanization) sealers
TP-6903 5/16a
can