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Engine Trouble in General: Inspection

WARNING: This page is about a different variant/trim than selected.
NOTE: "RANK" shown in the chart refers to the possibility of the cause of trouble in order 'Very often" to "Rarely"
SYMPTOMS CHART

Symptoms Problem parts etc. Possible cause RANK
1. Engine does not start.  
1) Starter does not turn. Starter Defective battery-to-starter harness B
Defective starter switch C
Defective inhibitor switch C
Defective starter B
Battery Improper connection of the terminal A
Run-down battery A
Defective charging system B
Friction Seizure of crankshaft and connecting rod bearing C
Seized camshaft C
Seized or stuck piston and cylinder C
2) Initial combustion does not occur. Starter Defective starter C
Engine control system < Ref. to BASIC DIAGNOSTIC PROCEDURE . > A
Fuel line Defective fuel pump and relay A
Lack of or insufficient fuel B
Belt Trouble B
Defective timing B
Compression Incorrect valve clearance C
Loosened spark plug or defective gasket C
Loosened cylinder head bolt or defective gasket C
Improper valve sealing C
Defective valve stem C
Worn or broken valve spring B
Worn or stuck piston rings, cylinder and piston C
Incorrect valve timing B
Improper engine oil (low viscosity) B
3) Initial combustion occurs. Engine control system < Ref. to BASIC DIAGNOSTIC PROCEDURE . > A
Intake system Defective intake manifold gasket B
Defective throttle body gasket B
Fuel line Defective fuel pump and relay C
Clogged fuel line C
Lack of or insufficient fuel B
Belt Trouble B
Defective timing B
Compression Incorrect valve clearance C
Loosened spark plug or defective gasket C
Loosened cylinder head bolt or defective gasket C
Improper valve sealing C
Defective valve stem C
Worn or broken valve spring B
Worn or stuck piston rings, cylinder and piston C
Incorrect valve timing B
Improper engine oil (low viscosity) B
4) Engine stalls after initial combustion. Engine control system < Ref. to BASIC DIAGNOSTIC PROCEDURE . > A
Intake system Loosened or cracked intake duct B
Loosened or cracked PCV hose C
Loosened or cracked vacuum hose C
Defective intake manifold gasket B
Defective throttle body gasket B
Dirty air cleaner element C
Fuel line Clogged fuel line C
Lack of or insufficient fuel B
Belt Trouble B
Defective timing B
Compression Incorrect valve clearance C
Loosened spark plug or defective gasket C
Loosened cylinder head bolt or defective gasket C
Improper valve sealing C
Defective valve stem C
Worn or broken valve spring B
Worn or stuck piston rings, cylinder and piston C
Incorrect valve timing B
Improper engine oil (low viscosity) B
2. Rough idle and engine stall Engine control system < Ref. to BASIC DIAGNOSTIC PROCEDURE . > 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 C
Loosened oil filler cap B
Dirty air cleaner element C
Fuel line Defective fuel pump and relay C
Clogged fuel line C
Lack of or insufficient fuel B
Belt Defective timing C
Compression Incorrect valve clearance B
Loosened spark plug or defective gasket B
Loosened cylinder head bolt or defective gasket B
Improper valve sealing B
Defective valve stem C
Worn or broken valve spring B
Worn or stuck piston rings, cylinder and piston B
Incorrect valve timing A
Improper engine oil (low viscosity) B
Lubrication system Incorrect oil pressure B
Defective rocker cover gasket C
Cooling system Overheating C
Others Evaporative emission control system malfunction A
Stuck or damaged throttle valve B
3. Low output, hesitation and poor acceleration Engine control system < Ref. to BASIC DIAGNOSTIC PROCEDURE . > A
Intake system Loosened or cracked intake duct A
Loosened or cracked PCV hose A
Loosened or cracked vacuum hose B
Defective intake manifold gasket B
Defective throttle body gasket B
Defective PCV valve B
Loosened oil filler cap B
Dirty air cleaner element A
Fuel line Defective fuel pump and relay B
Clogged fuel line B
Lack of or insufficient fuel C
Belt Defective timing B
Compression Incorrect valve clearance B
Loosened spark plug or defective gasket B
Loosened cylinder head bolt or defective gasket B
Improper valve sealing B
Defective valve stem C
Worn or broken valve spring B
Worn or stuck piston rings, cylinder and piston C
Incorrect valve timing A
Improper engine oil (low viscosity) B
Lubrication system Incorrect oil pressure B
Cooling system Overheating C
Over-cooling C
Others Evaporative emission control system malfunction A
4. Surging Engine control system < Ref. to BASIC DIAGNOSTIC PROCEDURE . > 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
Belt 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
Worn or broken valve spring C
Worn or stuck piston rings, cylinder and piston C
Incorrect valve timing A
Improper engine oil (low viscosity) B
Cooling system Overheating B
Others Evaporative emission control system malfunction C
5. Engine does not return to idle. Engine control system < Ref. to BASIC DIAGNOSTIC PROCEDURE . > A
Intake system Loosened or cracked vacuum hose A
Others Stuck or damaged throttle valve A
6. Dieseling (Run-on) Engine control system < Ref. to BASIC DIAGNOSTIC PROCEDURE . > A
Cooling system Overheating B
Others Evaporative emission control system malfunction B
7. After burning in exhaust system Engine control system < Ref. to 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 plug or defective gasket C
Loosened cylinder head bolt or defective gasket C
Improper valve sealing 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 Evaporative emission control system malfunction C
8. Knocking Engine control system < Ref. to 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 consumption 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 gasket 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
10. Excessive fuel consumption. Engine control system < Ref. to BASIC DIAGNOSTIC PROCEDURE . > A
Intake system Dirty air cleaner element A
Belt 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
Worn or broken valve spring C
Worn or stuck piston rings, cylinder and piston B
Incorrect valve timing B
Lubrication system Incorrect oil pressure C
Cooling system Over-cooling C
A - Very often
B - Sometimes
C - Rarely