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This Section provides an easy reference guide to the more common problems which may occur during the operation of your vehicle.

These problems and possible causes are grouped under various components or systems; i.e. Engine, Cooling system, etc.

Remember that successful troubleshooting is not a mysterious "black art" practiced only by professional mechanics; it's simply the result of a bit of knowledge combined with an intelligent and systematic approach to the problem. Always work by a process of elimination, starting with the simplest solution and working through to the most complex - and never overlook the obvious. Anyone can forget to fill the gas tank or leave the lights on overnight, so don't assume that you are above such oversights. Finally, always get clear in your mind why a problem has occurred and take steps to ensure that it doesn't happen again. If the electrical system fails because of a poor connection, check all other connections in the system to make sure that they don't fail as well; if a particular fuse continues to blow, find out why - don't just go on replacing fuses. Remember, failure of a small component can often be indicative of potential failure or incorrect functioning of a more important component or system.

Contents 1 Engine and engine performance 1.1 Engine will not rotate when attempting to start 1.2 Engine rotates but will not start 1.3 Starter motor operates without rotating engine 1.4 Engine hard to start when cold 1.5 Engine hard to start when hot 1.6 Starter motor noisy or excessively rough in engagement 1.7 Engine starts but stops immediately 1.8 Engine “Lopes” while idling or idles erratically 1.9 Engine misses at idle speed 1.10 Engine misses throughout the driving speed range 1.11 Engine stalls 1.12 Engine lacks power 1.13 Engine backfires 1.14 Pinging or knocking engine sounds during acceleration or uphill 1.15 Engine diesels (continues to run after switching off 2 Engine electrical system 2.1 Battery will not hold a charge 2.2 Alternator light fails to go out 2.3 Ignition light fails to come on when key is turned on 2.4 "CHECK ENGINE" light comes on 3 Fuel system 3.1 Excessive fuel consumption 3.2 Fuel leakage and/or fuel odor 4 Cooling system 4.1 Overheating 4.2 Overcooling 4.3 External coolant leakage 4.4 Internal coolant leakage 4.5 Coolant loss 4.6 Poor coolant circulation 5 Clutch 5.1 Fails to release (pedal pressed to the floor - shift lever does not move freely in and out of Reverse) 5.2 Clutch slips (engine speed increases with no increase in vehicle speed) 5.3 Grabbing (chattering) as clutch is engaged 5.4 Squeal or rumble with clutch fully engaged (pedal released) 5.5 Squeal or rumble with clutch fully disengaged (pedal depressed) 5.6 Clutch pedal travels to floor – no pressure or very little resistance

Engine and engine performance

Engine will not rotate when attempting to start

1. Battery terminal connections loose or corroded. Check the cable terminals at the battery; tighten the cable or remove corrosion as necessary.
2. Battery discharged or faulty. If the cable connections are clean and tight on the battery turn the key to the On position and switch on the headlights and/or windshield wipers. If they fail to function, the battery is discharged.
3. Automatic transaxle not completely engaged in Park or clutch not completely
4. Broken, loose or disconnected wiring in the starting circuit. Inspect all wiring and connectors at the battery, starter solenoid, neutral start switch and ignition switch.
5. Starter motor pinion jammed in the flywheel ring gear. If manual transaxle, place transaxle in gear and rock the vehicle to manually turn the engine. Remove starter and inspect pinion and flywheel at earliest convenience.
6. Starter solenoid faulty . See Engine Electrical.
7. Starter motor faulty . See Engine Electrical.
8. Ignition switch faulty (Chapter 12).

Engine rotates but will not start

1. Fuel tank empty.
2. Battery discharged (engine rotates slowly). Check the operation of electrical components as described in previous Section.
3. Battery terminal connections loose or corroded. See previous Section .
4. Carburetor flooded and/or fuel level in carburetor incorrect. This will usually be accompanied by a strong fuel odor from under the hood. Wait a few minutes, depress the accelerator pedal all the way to the floor and attempt to start the engine.
5. Choke control inoperative – carbureted models . See Routine Maintenance.
6. Fuel not reaching carburetor or fuel injection system . See Fuel System Repair.
7. Fuel injector or fuel pump faulty (fuel injected vehicles) . See Fuel System Repair.
8. Excessive moisture on, or damage to, ignition components . See Engine Electrical.
9. Worn, faulty or incorrectly gapped spark plugs . See Routine Maintenance.
10. Broken, loose or disconnected wiring in the starting circuit (see previous Section).
11. Distributor loose, causing ignition timing to change (HE1 ignition systems only). Turn the distributor as necessary to start engine, then set ignition timing as soon as possible . See Routine Maintenance.
12. Broken, loose or disconnected wires at the ignition coil(s) or faulty coil(s) . See Engine Electrical.
13. Broken or loose timing chain (OHV engines only) . See Engine Repair.
14. Broken or stripped timing belt (OHC engines only) . See Engine Repair.

Starter motor operates without rotating engine

1. Starter pinion sticking. Remove the starter . See Engine Electrical and inspect.
2. Starter pinion or flywheel teeth worn or broken. Remove the cover at the rear of the engine and inspect.

Engine hard to start when cold

1. Battery discharged or low. Check as described in Section 1.
2. Choke control inoperative or out of adjustment - carbureted models . See Fuel System Repair.
3. Carburetor flooded (see Section 2).
4. Insufficient fuel supply reaching the carburetor or fuel-injection system - check fuel pressure . See Fuel System Repair.
5. Leaky fuel injectors, fuel lines or fuel pump outlet check valve, causing fuel pressure to bleed down while the vehicle is sitting

(multi-port fuel injection systems) . See Fuel System Repair.

1. Carburetor/fuel injection system malfunctioning . See Fuel System Repair.
2. Distributor rotor carbon tracked . See Routine Maintenance.

Engine hard to start when hot

1. Choke sticking in the closed position -carbureted models - . See Routine Maintenance.
2. Carburetor flooded (see Section 2).
3. Air filter clogged . See Routine Maintenance.
4. Malfunction in the carburetor or fuel injection system . See Fuel System Repair.
5. Insufficient fuel supply reaching the carburetor or fuel injection system. Check the fuel pressure . See Fuel System Repair.
6. Leaky fuel injectors, fuel lines or fuel pump outlet check valve, causing fuel pressure to bleed down while the vehicle is sitting (multi-port fuel injection systems) . See Fuel System Repair.

Starter motor noisy or excessively rough in engagement

1. Pinion or flywheel gear teeth worn or broken. Remove the cover at the rear of the engine (if so equipped) and inspect.
2. Starter motor mounting bolts loose or missing.

Engine starts but stops immediately

1. Loose or faulty electrical connections at distributor, coil or alternator.
2. Insufficient fuel reaching the carburetor/fuel injector(s) - check the fuel pressure . See Fuel System Repair.
3. Vacuum leak at the gasket surfaces of the intake manifold and/or carburetor/throttle body. Make sure that all mounting bolts (nuts)

are re-tightened securely and that all vacuum hoses connected to the carburetor/fuel injection unit(s) and manifold are positioned properly and in good condition.

Engine “Lopes” while idling or idles erratically

1. Vacuum leakage. Check mounting bolts (nuts) at the carburetor/throttle body and intake manifold for tightness. Make sure that all vacuum hoses are connected and in good condition. Use a length of fuel hose held against your ear to listen for vacuum leaks while the engine is running. A hissing sound will be heard. A soapy water solution will also detect leaks. Check the carburetor/throttle body and intake manifold gasket surfaces. Also check the points where the injectors are attached to the intake ports (multi-port fuel injection).
2. Leaking EGR valve or plugged PCV valve (see Chapters 1 and 6).
3. Air filter clogged . See Routine Maintenance.
4. Fuel pump not delivering sufficient fuel to the carburetor/fuel injector(s) - check the fuel pressure . See Fuel System Repair.
5. Carburetor out of adjustment . See Fuel System Repair or clogged fuel injectors.
6. Leaking head gasket. If this is suspected, take the vehicle to a repair shop or dealer where the engine can be pressure checked.
7. Timing chain and/or gears worn . See Engine Repair.
8. Camshaft lobes worn . See Engine Repair.

Engine misses at idle speed

1. All the causes listed in the previous Section, plus:
2. Spark plugs worn or not gapped properly . See Routine Maintenance.
3. Faulty spark plug wires . See Routine Maintenance.
4. Choke not operating properly – carbureted models . See Routine Maintenance.

Engine misses throughout the driving speed range

1. Fuel filter clogged and/or impurities in the fuel system . See Routine Maintenance. Also check the fuel pressure . See Fuel System Repair.
2. Clogged fuel injectors.
3. Faulty or incorrectly gapped spark plugs . See Routine Maintenance.
4. Incorrect ignition timing . See Routine Maintenance.
5. On early models with HEI ignition, check for cracked distributor cap, disconnected distributor wires and damaged distributor components . See Routine Maintenance.
6. Leaking spark plug wires . See Routine Maintenance.
7. Faulty emissions system components . See Engine Controls.
8. Low or uneven cylinder compression pressures. Remove spark plugs and test compression with gauge . See Routine Maintenance.
9. Weak or faulty ignition system . See Engine Electrical.
10. Vacuum leaks at carburetor/throttle body, intake manifold or vacuum hoses (see Section 8).

Engine stalls

1. Idle speed incorrect . See Routine Maintenance or automatic idle speed control circuit malfunctioning.
2. Fuel filter clogged and/or water and impurities in the fuel system . See Routine Maintenance.
3. Choke improperly adjusted or sticking -carbureted models - . See Routine Maintenance.
4. Distributor components damp or damaged- early models with HEI ignition systems . See Engine Electrical.
5. Faulty emissions system components . See Engine Controls.
6. Faulty or incorrectly gapped spark plugs . See Routine Maintenance. Also check spark plug wires . See Routine Maintenance.
7. Vacuum leak at the carburetor/throttle body, intake manifold or vacuum hoses. Check as described in Section 8.
8. If the engine stalls after cruising (where the torque converter clutch TCC] engages), but then re-starts, the problem could be a faulty TCC solenoid. If the solenoid sticks closed, the clutch will remain engaged when the vehicle is coming to a stop, which will stall the engine. Refer to the Haynes Automatic Transmission and Transaxle Overhaul Manual for details on this relatively simple repair.

Engine lacks power

1. Incorrect ignition timing - early models with HEI ignition systems - . See Routine Maintenance.
2. Excessive play in distributor shaft (early models with HEI ). At the same time, check for worn rotor, faulty distributor cap, wires, etc. (Chapters 1 and 5).
3. Faulty or incorrectly gapped spark plugs . See Routine Maintenance.
4. Carburetor/fuel injection system excessively worn . See Fuel System Repair.
5. Faulty ignition coil(s) . See Engine Electrical.
6. Brakes binding . See Routine Maintenance.
7. Automatic transaxle fluid level incorrect . See Routine Maintenance.
8. Clutch slipping . See Driveline Repair.
9. Fuel filter clogged and/or impurities in the fuel system . See Routine Maintenance.
10. Emissions control system not functioning properly . See Engine Controls.
11. Use of substandard fuel. Fill tank with proper octane fuel.
12. Low or uneven cylinder compression pressures. Test with compression tester, which will detect leaking valves and/or blown head gasket . See Routine Maintenance.

Engine backfires

1. Emissions system not functioning properly . See Engine Controls.
2. Ignition timing incorrect - early models with HEI ignition systems . See Routine Maintenance.
3. Faulty secondary ignition system (cracked spark plug insulator, faulty plug wires, distributor cap and/or rotor) (Chapters 1 and 5).
4. Carburetor/fuel injection system in need of adjustment or worn excessively . See Fuel System Repair. A clogged fuel injector may also cause this problem.
5. Vacuum leak at carburetor/throttle body, intake manifold or vacuum hoses. Check as described in Section 8.
6. Valves sticking or burned . See Engine Repair.

Pinging or knocking engine sounds during acceleration or uphill

1. Incorrect grade of fuel. Fill tank with fuel of the proper octane rating .
2. Ignition timing incorrect . See Routine Maintenance.
3. Carburetor/fuel injection system excessively worn . See Fuel System Repair.
4. Improper spark plugs. Check plug type against Emissions Control Information label located in engine compartment. Also check plugs and wires for damage . See Routine Maintenance.
5. Worn or damaged distributor components . See Engine Electrical.
6. Faulty emissions system . See Engine Controls.
7. Vacuum leak. Check as described Section 8.

Engine diesels (continues to run after switching off

1. Vacuum leaks. Check as described Section 8.
2. Idle speed too high . See Routine Maintenance.
3. Ignition timing incorrectly adjusted . See Routine Maintenance.
4. Thermo-controlled air cleaner heat valve not operating properly . See Engine Controls.
5. Excessive engine operating temperature Probable causes of this are malfunctioning thermostat, clogged radiator, faulty water pump . See HVAC Repair.

Engine electrical system

Battery will not hold a charge

1. Alternator drivebelt defective or not adjusted properly . See Routine Maintenance.
2. Electrolyte level low or battery discharged . See Routine Maintenance.
3. Battery terminals loose or corroded . See Routine Maintenance.
4. Alternator not charging properly (Chapter 5
5. Loose, broken or faulty wiring in the charging circuit . See Engine Electrical.
6. Short in vehicle wiring causing a continual drain on battery
7. Battery defective internally.

Alternator light fails to go out

1. Fault in alternator or charging circuit . See Engine Electrical.
2. Alternator drivebelt defective or not properly adjusted . See Routine Maintenance.

Ignition light fails to come on when key is turned on

1. Warning light bulb defective (Chapter 12).
2. Alternator faulty . See Engine Electrical.
3. Fault in the printed circuit, dash wiring or bulb holder (Chapter 12).

"CHECK ENGINE" light comes on

1. Check for trouble codes stored in the ECM (see Chapter 6).

Fuel system

Excessive fuel consumption

1. Dirty or clogged air filter element . See Routine Maintenance
2. Incorrectly set ignition timing – early models with HE1 ignition system . See Routine Maintenance.
3. Choke sticking or improperly adjusted - carbureted models . See Routine Maintenance.
4. Emissions system not functioning properly . See Engine Controls.
5. Carburetor/fuel injection internal parts excessively worn or damaged . See Fuel System Repair.
6. Low tire pressure or incorrect tire size . See Routine Maintenance.

Fuel leakage and/or fuel odor

1. Leak in a fuel feed or vent line . See Fuel System Repair.
2. Tank overfilled. Fill only to automatic shut-off.
3. Emissions system filter clogged . See Routine Maintenance.
4. Vapor leaks from system lines . See Fuel System Repair.
5. Carburetor/fuel injection internal parts excessively worn . See Fuel System Repair.

Cooling system

Overheating

1. Insufficient coolant in system . See Routine Maintenance.
2. Water pump drivebelt defective or not adjusted properly . See Routine Maintenance.
3. Radiator core blocked or radiator grille dirty and restricted . See HVAC Repair.
4. Thermostat faulty . See HVAC Repair.
5. Fan blades broken or cracked.
6. Radiator cap not maintaining proper pressure. Have cap pressure tested by a gas station.
7. Ignition timing incorrect - models with a distributor . See Routine Maintenance.

Overcooling

1. Thermostat faulty . See HVAC Repair.
2. Inaccurate temperature gauge or sending unit (Chapter 12).

External coolant leakage

1. Deteriorated or damaged hoses or loose clamps. Replace hoses and/or tighten clamps at hose connections (Chapter 11).
2. Water pump seals defective. If this is the case, water will drip from the "weep" hole in the water pump body . See HVAC Repair.
3. Leakage from radiator core or header tank. This will require the radiator to be professionally repaired (see Chapter 3 for removal procedures) .
4. Engine drain plugs or water jacket core plugs leaking (see Chapter 2).

Internal coolant leakage

Note: lnternal coolant leaks can usually be detected by examining the oil. Check the dipstick and inside of the valve cover for water deposits and an oil consistency like that of a milkshake.

1. Leaking cylinder head gasket. Have the cooling system pressure tested.
2. Cracked cylinder bore or cylinder head. Dismantle engine and inspect . See Engine Repair.

Coolant loss

1. Too much coolant in system . See Routine Maintenance.
2. Coolant boiling away due to overheating (see Section 24).
3. Internal or external leakage (see Sections 26 and 27).
4. Faulty radiator cap. Have the cap pressure tested.

Poor coolant circulation

1. Inoperative water pump. A quick test is to pinch the top radiator hose closed with your hand while the engine is idling, then let it loose. You should feel the surge of coolant if the pump is working properly . See HVAC Repair.
2. Restriction in cooling system. Drain, flush and refill the system . See Routine Maintenance. If necessary, remove the radiator . See HVAC Repair and have it reverse flushed.
3. Water pump drivebelt defective or not adjusted properly . See Routine Maintenance.
4. Thermostat sticking . See HVAC Repair.

Clutch

Fails to release (pedal pressed to the floor - shift lever does not move freely in and out of Reverse)

1. lmproper linkage free play adjustment.
2. Clutch cable excessively stretched or damaged . See Driveline Repair.
3. Air in clutch hydraulic release system . See Driveline Repair.
4. Leaking clutch hydraulic release system . See Driveline Repair.
5. Clutch fork off ball stud.
6. Clutch plate warped or damaged . See Driveline Repair.

Clutch slips (engine speed increases with no increase in vehicle speed)

1. Linkage out of adjustment . See Driveline Repair.
2. Clutch plate oil soaked or lining worn. Remove clutch . See Driveline Repair and inspect.
3. Clutch plate not seated. It may take 30 or 40 normal starts for a new one to seat.

Grabbing (chattering) as clutch is engaged

1. Oil on clutch plate lining. Remove . See Driveline Repair and inspect. Correct any leakage source.
2. Worn or loose engine or transaxle mounts. These units move slightly when clutch is released. Inspect mounts and bolts.
3. Worn splines on clutch plate hub. Remove clutch components . See Driveline Repair and inspect.
4. Warped pressure plate or flywheel. Remove clutch components and inspect.

Squeal or rumble with clutch fully engaged (pedal released)

1. lmproper adjustment; no freeplay . See Routine Maintenance.
2. Release bearing binding on transaxle bearing retainer. Remove clutch components . See Driveline Repair and check bearing. Remove any burrs or nicks, clean and relubricate before reinstallation.
3. Weak linkage return spring. Replace the spring.

Squeal or rumble with clutch fully disengaged (pedal depressed)

1. Worn, defective or broken release bearing . See Driveline Repair.
2. Worn or broken pressure plate springs (or diaphragm fingers) . See Driveline Repair.

Clutch pedal travels to floor – no pressure or very little resistance

1. Clutch cable damaged or linkage binding.
2. Clutch hydraulic release system leaking or faulty . See Driveline Repair
3. No fluid in clutch hydraulic release system reservoir . See Routine Maintenance.
4. Broken release bearing or fork . See Driveline Repair.
5. Sticking clutch release diaphragm fingers . See Driveline Repair.