Kia Rio: Electric Oil Pump: Description
This transaxle has a standard Mechanical Oil Pump (MOP) linked to the
input shaft to generates oil pressure when input shaft rotates.
But, this transaxle equipped with ISG system also has an Electric Oil
Pump (EOP). Because the ISG system features Auto-Stop which starts and stops
the engine as needed. The Auto-Stop feature prevents the Mechanical Oil Pump
(MOP) from operating and building enough pressure for the transaxle to operate.
When the vehicle comes to a stop with the engine off, Mechanical Oil Pump (MOP)
cannot generate sufficient oil pressure during the initial startup or during
low speed driving.
For these reasons, the Electric Oil Pump (EOP) takes on this role as an
additional device that can generate the required oil pressure when the vehicle
comes to a stop or during low speed driving. The Electric Oil Pump (EOP) supplies
oil pressure to the Under Drive Brake (UD/B).

1.
Disconnect the battery negative terminal.
2.
Remove the air duct and air cleaner assembly. (Refer to EM group)
3.
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See also:
Description
Crankshaft Position Sensor (CKPS) detects the crankshaft position and
is one of the most important sensors of the engine control system. If there
is no CKPS signal input, the engine may stop ...
Component Location
1. Start Stop Button(SSB)
2. FOB key
3. Smart key unit
4. Interior antenna 1
5. Interior antenna 2
6. Trunk antenna
7. Door handle & door antenna
8. Bumper ante ...
Fuel Pressure Test (Low pressure system)
1.
Release the residual pressure in fuel line (Refer to the Fuel
Delivery System - Repair Procedures - "Release Residual Pressure in
Fuel Line").
...