HOSE AS 3534831 - Caterpillar

Probable Causes
Incorrect low idle setting
Faulty unit injector
Problem with the governor
Poor fuel quality
Air in fuelRecommended Repairs
Incorrect Low Idle Setting
Verify that the low idle speed setting is correct.Faulty Unit Injector
Inspect the unit injectors. Refer to Troubleshooting, "Unit Injector Misfire" and Troubleshooting, "Unit Injector".Problem With the Governor
Ensure that the governor is operating properly. Refer to Troubleshooting, "Governor Instability".Poor Fuel Quality
Ensure that there is good, clean fuel in the tank. When possible, interview the operator in order to determine if fuel quality is in question. Try to determine if the engine started misfiring soon after refueling. Refer to Troubleshooting, "Fuel Quality".Air in the Fuel
Check for air in the fuel system. Refer to Troubleshooting, "Air in Fuel".