ME(H6DO)-87
Engine Trouble in General
MECHANICAL
4. Surging Engine control system A
Intake system Loosened or cracked intake duct A
Loosened or cracked PCV hose A
Loosened or cracked vacuum hose A
Defective intake manifold gasket B
Defective throttle body gasket B
Defective PCV valve B
Loosened oil filler cap B
Dirty air cleaner element B
Fuel line Defective fuel pump and relay B
Clogged fuel line B
Lack of or insufficient fuel C
Chain Defective timing B
Compression Incorrect valve clearance B
Loosened spark plug or defective gasket C
Loosened cylinder head bolt or defective gasket C
Improper valve sealing C
Defective valve stem C
Wor n or broken valve spr ing C
Wor n or stuck piston r ings, cylinder and piston C
Incorrect valve timing A
Improper engine oil (low viscosity) B
Tr o u b l e o f t a p p e t C
Tr o u b l e o f t a p p e t . I n c a s e n o i s e o c c u r s w i t h v a l v e m o v -
ing. Or the harness involved to oil switching solenoid
valve, variable valve lift diagnosis oil pressure switch
and variable valve lift has trouble in a past.
B
Cooling system Over-heating B
Others Evaporative emission control system malfunction C
5. Engine does not return to
idle.
Engine control system A
Intake system Loosened or cracked vacuum hose A
Others Stuck or damaged throttle valve A
6. Dieseling (Run-on) Engine control system A
Cooling system Over-heating B
Others Evaporative emission control system malfunction B
Symptom Problem parts etc. Possible cause RANK
ME(H6DO)-88
Engine Trouble in General
MECHANICAL
7. After burning in exhaust
system
Engine control system A
Intake system Loosened or cracked intake duct C
Loosened or cracked PCV hose C
Loosened or cracked vacuum hose B
Defective PCV valve B
Loosened oil filler cap C
Chain Defective timing B
Compression Incorrect valve clearance B
Loosened spark plug or defective gasket C
Loosened cylinder head bolt or defective gasket C
Improper valve sealing B
Defective valve stem C
Wor n or broken valve spr ing C
Wor n or stuck piston r ings, cylinder and piston C
Incorrect valve timing A
Tr o u b l e o f t a p p e t C
Tr o u b l e o f t a p p e t . I n c a s e n o i s e o c c u r s w i t h v a l v e m o v -
ing. Or the harness involved to oil switching solenoid
valve, variable valve lift diagnosis oil pressure switch
and variable valve lift has trouble in a past.
B
Lubrication system Incorrect oil pressure C
Cooling system Over-cooling C
Others Evaporative emission control system malfunction C
8. Knocking Engine control system A
Intake system Loosened oil filler cap B
Chain Defective timing B
Compression Incorrect valve clearance C
Incorrect valve timing B
Tr o u b l e o f t a p p e t C
Tr o u b l e o f t a p p e t . I n c a s e n o i s e o c c u r s w i t h v a l v e m o v -
ing. Or the harness involved to oil switching solenoid
valve, variable valve lift diagnosis oil pressure switch
and variable valve lift has trouble in a past.
B
Cooling system Over-heating A
9. Excessive engine oil con-
sumption
Intake system Loosened or cracked PCV hose A
Defective PCV valve B
Loosened oil filler cap C
Compression Defective valve stem A
Wor n or stuck piston r ings, cylinder and piston A
Lubrication system Loosened oil pump attaching bolts and defective gas-
ket
B
Defective oil filter o-ring B
Defective crankshaft oil seal B
Defective rocker cover gasket B
Loosened oil drain plug or defective gasket B
Loosened oil pan fitting bolts or defective oil pan B
Symptom Problem parts etc. Possible cause RANK
PM-14
Engine Coolant
PERIODIC MAINTENANCE SERVICES
10.Engine Coolant
A: REPLACEMENT
1. REPLACEMENT OF ENGINE COOLANT
WARNING:
The radiator is of the pressurized type. Do not
attempt to open the radiator cap immediately
after the engine has been stopped.
1) Lift-up the vehicle.
2) Remove the under cover.
3) Place a container under drain pipe.
4) Remove the drain cock to drain engine coolant
into container.
5) For quick draining, open the radiator cap.
NOTE:
Be careful not to spill coolant on the floor.
6) Drain the coolant from reservoir tank.
7) Tighten the radiator drain cock securely after
draining coolant.
8) Pour cooling system conditioner through the fill-
er neck.
Cooling system protective agent:
Cooling system conditioner (Part number:
SOA345001)
9) Fill engine coolant into the reservoir tank up to
“FULL” level.
Recommended engine coolant:
Refer to “RM” section.
ANT, RECOMMENDED MATERIALS, Recom-
mended Materials.>
Coolant capacity (fill up to “FULL” level):
Approx. 7.4 2 (7.8 US qt, 6.5 Imp qt)
NOTE:
The SUBARU Genuine Coolant containing anti-
freeze and anti-rust agents is especially made for
SUBARU engine, which has an aluminum crank-
case. Always use SUBARU Genuine Coolant,
since other coolant may cause corrosion.
10) Close the radiator cap, and start the engine.
Race 5 to 6 times at 3,000 rpm or less, then stop
the engine. (Complete this operation within 40 sec-
onds.)
11) Wait for one minute after the engine stops, then
open the radiator cap. If the engine coolant level
drops, add engine coolant into radiator up to the fill-
er neck position.
12) Perform the procedures 10) and 11) again.
13) Install the radiator cap and reservoir tank cap
properly.
14) Start the engine and operate the heater at max-
imum hot position and the blower speed setting to
“LO”.
15) Run the engine at 2,000 rpm or less until radia-
tor fan starts and stops.
NOTE:
•Be careful with the engine coolant temperature
gauge to prevent overheating.
•If the radiator hose becomes harden by engine
coolant pressure at this time, air purge seems to be
mostly completed.
16) Stop the engine and wait until the engine cool-
ant temperature lowers to 30°C (86°F).
17) Open the radiator cap. If the engine coolant lev-
el drops, add engine coolant into the coolant filler
tank up to the filler neck position and the reservoir
tank to “FULL” level.
18) Install the radiator cap and reservoir tank cap
properly.
19) Set the heater setting to maximum hot position
and the blower speed setting to “LO” and start the
engine. Perform racing at less than 3,000 rpm. If
the flowing sound is heard from heater core, repeat
the procedures from step 10).
CO-00248