I have a Yale GLP030 Forklift - pneumatic tire, propane fueled. There is a rectangular plastic box along the right side of the machine frame just ahead of the rad. The cable from the throttle pedal goes into this box and another cable comes out and goes to the throttle body lever on the propane fuel system. Lately there is a strange noise coming from this box when the key is first turned on and also for a little while after starting. Sounds a bit like a buzzer or a horn that is not working quite right and sounds "Sick" or maybe a relay that the contacts are cycling on and off real fast. The forklift still starts and runs fine and the sound goes away after 10 seconds or so.

Not sure what this box is - was wondering if it could be an electric governor for the engine or a rpm limit protection since it is in the middle of the throttle cable - somewhat like the box for cruise control on older cars before electronic fuel injection.

Appreciate if anyone has any info on what this component is and what might be making the noise.