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Symptoms And Causes: Inspection

WARNING: This page is about a different variant/trim than selected.
NOTE: The "RANK" shown in the chart shows the possibilities of the cause of trouble in order from "Very often" to "Rarely".

A - Very often

B - Sometimes

C - Rarely

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 relay C
Defective inhibitor switch C
Defective starter B
Battery Improper connection of 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
Immobilizer system Ref. to IMMOBILIZER (DIAGNOSTICS)>BASIC DIAGNOSTIC PROCEDURE . A
2) Initial combustion does not occur. Starter Defective starter C
Engine control system Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>BASIC DIAGNOSTIC PROCEDURE . A
Fuel line Defective fuel pump and relay A
Clogged fuel line C
Lack of fuel or insufficient fuel B
Timing chain Trouble B
Defective timing B
Compression Incorrect cam clearance C
Loosened spark plug or defective gasket C
Loosened cylinder head bolt or defective cylinder head gasket C
Improper valve sealing C
Defective valve stem C
Worn or broken valve spring B
Worn or stuck piston rings, cylinder liner and piston C
Incorrect valve timing B
Improper engine oil (low viscosity) B
3) Initial combustion occurs. Engine control system Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>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 fuel or insufficient fuel B
Timing chain Trouble B
Defective timing B
Compression Incorrect cam clearance C
Loosened spark plug or defective gasket C
Loosened cylinder head bolt or defective cylinder head gasket C
Improper valve sealing C
Defective valve stem C
Worn or broken valve spring B
Worn or stuck piston rings, cylinder liner and piston C
Incorrect valve timing B
Improper engine oil (low viscosity) B
4) Engine stalls after initial combustion. Engine control system Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>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
Defective electronic air by-pass valve C
Fuel line Clogged fuel line C
Lack of fuel or insufficient fuel B
Timing chain Trouble B
Defective timing B
Compression Incorrect cam clearance C
Loosened spark plug or defective gasket C
Loosened cylinder head bolt or defective cylinder head 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 ENGINE (DIAGNOSTICS) (H4DOTC)>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
Defective electronic air by-pass valve C
Fuel line Defective fuel pump and relay C
Clogged fuel line C
Lack of fuel or insufficient fuel B
Timing chain Defective timing C
Compression Incorrect cam clearance B
Loosened spark plug or defective gasket B
Loosened cylinder head bolt or defective cylinder head 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 Over-heating 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 ENGINE (DIAGNOSTICS) (H4DOTC)>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
Defective electronic air by-pass valve C
Fuel line Defective fuel pump and relay B
Clogged fuel line B
Lack of fuel or insufficient fuel C
Timing chain Defective timing B
Compression Incorrect cam clearance B
Loosened spark plug or defective gasket B
Loosened cylinder head bolt or defective cylinder head 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 Over-heating C
Over-cooling C
Others Evaporative emission control system malfunction A
4. Surging Engine control system Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>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
Defective electronic air by-pass valve C
Fuel line Defective fuel pump and relay B
Clogged fuel line B
Lack of fuel or insufficient fuel C
Timing chain Defective timing B
Compression Incorrect cam clearance B
Loosened spark plug or defective gasket C
Loosened cylinder head bolt or defective cylinder head 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 Over-heating B
Others Evaporative emission control system malfunction C
5. Engine does not return to idle. Engine control system Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>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 ENGINE (DIAGNOSTICS) (H4DOTC)>BASIC DIAGNOSTIC PROCEDURE . A
Cooling system Over-heating B
Others Evaporative emission control system malfunction B
7. After burning in exhaust system Engine control system Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>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
Defective electronic air by-pass valve C
Timing chain Defective timing B
Compression Incorrect cam clearance B
Loosened spark plug or defective gasket C
Loosened cylinder head bolt or defective cylinder head 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 ENGINE (DIAGNOSTICS) (H4DOTC)>BASIC DIAGNOSTIC PROCEDURE . A
Intake system Loosened oil filler cap B
Timing chain Defective timing B
Compression Incorrect cam clearance C
Incorrect valve timing B
Cooling system Over-heating 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 chain cover attaching bolts and defective gasket B
Defective oil filter gasket B
Defective crankshaft oil seal B
Defective rocker cover gasket B
Loosened oil drain plug or defective gasket B
Loosened oil pan mounting bolt or defective oil pan B
10. Excessive fuel consumption Engine control system Ref. to ENGINE (DIAGNOSTICS) (H4DOTC)>BASIC DIAGNOSTIC PROCEDURE . A
Intake system Dirty air cleaner element A
Timing chain Defective timing B
Compression Incorrect cam clearance B
Loosened spark plug or defective gasket C
Loosened cylinder head bolt or defective cylinder 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