Subaru Impreza 2004 - Page 189

ME(H4SO)-93
MECHANICAL
Engine Trouble in General
5. Engine does not return to
idle.
Engine control system <Ref. to EN(H4SO)(diag)-2, Basic Diagnostic Procedure.> or
<Ref. to EN(H4SOw/oOBD)(diag)-2, Basic Diagnostic Procedure.>
A
Intake system Loosened or cracked vacuum hose A
Others Stuck or damaged throttle valve A
Accelerator cable out of adjustment B
6. Dieseling (Run-on) Engine control system <Ref. to EN(H4SO)(diag)-2, Basic Diagnostic Procedure.> or
<Ref. to EN(H4SOw/oOBD)(diag)-2, Basic Diagnostic Procedure.>
A
Cooling system Overheating B
Others Malfunction of evaporative emission control system B
7. After burning in exhaust
system
Engine control system <Ref. to EN(H4SO)(diag)-2, Basic Diagnostic Procedure.> or
<Ref. to EN(H4SOw/oOBD)(diag)-2, Basic Diagnostic Procedure.>
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
Belt Defective timing B
Compression Incorrect valve clearance B
Loosened spark plugs or defective gasket C
Loosened cylinder head bolts or defective gasket C
Improper valve seating B
Defective valve stem C
Worn or broken valve spring C
Worn or stuck piston rings, cylinder and piston C
Incorrect valve timing A
Lubrication system Incorrect oil pressure C
Cooling system Over cooling C
Others Malfunction of evaporative emission control system C
8. Knocking Engine control system <Ref. to EN(H4SO)(diag)-2, Basic Diagnostic Procedure.> or
<Ref. to EN(H4SOw/oOBD)(diag)-2, Basic Diagnostic Procedure.>
A
Intake system Loosened oil filler cap B
Belt Defective timing B
Compression Incorrect valve clearance C
Incorrect valve timing B
Cooling system Overheating 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
Worn or stuck piston rings, cylinder and piston A
Lubrication system Loosened oil pump attaching bolts and defective gas-
ket
B
Defective oil filter seal 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
TROUBLE PROBLEM PARTS, ETC. POSSIBLE CAUSE RANK