Diesel Engine
The combination water/power steering pump (1) on this vehicle is attached to the lower corner of the cylinder block on the left hand side.
The water/power steering pump (1) cannot be disassembled or serviced separately.
The water/power steering pump (1) is driven by the accessory drive's serpentine belt.
| 1-CONTROL ROD SEALS |
| 2-VACUUM SUPPLY FITTING |
| 3-IMPELLER |
| 4-COOLANT RETURN |
| 5-REGULATING VALVE |
| 6-RETURN SPRINGS |
| 7-EVACUATION ROOMS |
| 8-CONTROL RODS |
| 9-POWER DIAPHRAGM |
| 10-WATER PUMP PULLEY |
The water pump is turned on or off by vacuum. The Powertrain Control Module (PCM) actuates a switchover valve that turns vacuum supply to the water pump piston. A piston slides back and forth covering and uncovering a port used for coolant flow.
The controlling of the coolant flow helps manage temperature throughout the cooling system.
The water pump can be shut off if the following conditions exist:
- Engine speed is not achieved
- The fuel injection quantity in not achieved
- Intake air temperature is not reached
- Coolant temperature is not reached
- The A/C control unit does not request the heating mode