Subaru IMPREZA 2002 Service Manual page 286

ENGINE LUBRICATION SYSTEM TROUBLE IN GENERAL
LUBRICATION
Possible cause
1) Oil pressure switch
failure
Cracked diaphragm or oil leakage within switch
Broken sDrina or seized contacts
9. Engine Lubrication System
A: INSPECTION
Before performing diagnostics, make sure that the engine oil level is correct and no oil leakage exists.
Trouble in General
Corrective action
Replace.
ReDlaCe.
Trouble
2) Low oil pressure
1. Warning light remains
m.
Clogged oil passage Clean.
Excessive tip clearance and side clearance of oil
pump rotor and aear
Replace.
2. Warning light does
rlot go on.
3) No oil pressure
3. Warning light flickers
momentarily.
Broken pipe of oil strainer Replace.
Stuck oil pump rotor Replace.
1) Burn-out bulb
2)
Poor contact of switch contact Doints
I
Cloaaed oil filter
I
Replace.
I
Replace.
ReDlaCe.
I
Malfunction of oil by-pass valve in oil filter
I
Clean or replace.
I
I
I
Malfunction of oil relief valve in oil pump
I
Clean or replace.
I
Clogged oil strainer or broken pipe
I
Clean or replace.
I
I
Insufficient engine oil
I
Replenish.
I
3) Disconnection of wirina
I
Repair.
I
1)
Poor contact at terminals
2) Defective wiring harness
[
Repair.
I
Repair.
3) Low oil pressure
Check for the same
possible causes as
listed in 1
.-2).
LU-28