Noise from Injectors with Keyswitch ON
Note: This condition does not indicate an electronic system problem. Also, this condition does not indicate a problem with the injectors or the HEUI fuel system.
As part of the cold start strategy, the HEUI fuel system rapidly actuates the injector solenoids in order to warm the oil that is in the injectors. This rapid actuation of the solenoids produces a buzzing noise that can be heard outside the engine. This will occur before starting the engine while the keyswitch is in the ON position. This is a normal condition. There are no diagnostic codes or events that are associated with this condition. No fuel will be injected while this buzzing noise is present.
The buzzing noise will occur when the following conditions have been met:
- The engine is not running.
- The keyswitch is turned to the ON position.
- The air inlet heater is operating.
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