spark plugs CHERY TIGGO 2009 Service User Guide

Downloaded from www.Manualslib.com manuals search engine DIAGNOSIS & TESTING
Engine Performance Diagnostics
CONDITIONPOSSIBLE CAUSES CORRECTION
Engine Does Not Start 1. Weak battery.
2. Corroded or loose battery
connections.
3. Faulty starter.
4. Faulty coil(s) or control unit.
5. Incorrect spark plug gap.
6. Contamination in fuel system.
7. Faulty fuel pump.
8. Incorrect timing.1. Test battery. Charge or replace if
necessary.
2. Clean and tighten battery
connections. Apply a coat of light
mineral grease to terminals.
3. Test starting system. Check for
codes. (Refer to Appropriate
Diagnostic Information)
4. Test and replace as needed.
(Refer to Appropriate Diagnostic
Information)
5. Set gap.
6. Clean system and replace fuel
filter.
7. Test fuel pump and replace as
needed. (Refer to Appropriate
Diagnostic Information)
8. Check for a skipped timing belt.
Engine Stalls Or Idles Rough 1. Idle speed too low.
2. Incorrect fuel mixture.
3. Intake manifold leakage.
4. Faulty ignition coil(s).1. Test minimum air flow. (Refer to
Appropriate Diagnostic Information)
2. (Refer to Appropriate Diagnostic
Information)
3. Inspect intake manifold, manifold
gasket, and vacuum hoses.
4. Test and replace if necessary.
(Refer to Appropriate Diagnostic
Information)
Engine Loss Of Power 1. Dirty or incorrectly gapped spark
plugs.
2. Contamination in fuel system.
3. Faulty fuel pump.
4. Incorrect valve timing.
5. Leaking cylinder head gasket.
6. Low compression.
7. Burned, warped, excessive
clearance, or pitted valves.
8. Plugged or restricted exhaust
system.
9. Faulty ignition coil(s).
10. Burned spark plugs.1. Clean spark plugs and set gap.
2. Clean system and replace fuel
filter.
3. Test and replace if necessary.
(Refer to Appropriate Diagnostic
Information)
4. Correct valve timing.
5. Replace cylinder head gasket.
6. Test compression of each
cylinder.
7. Replace valves.
8. Perform exhaust restriction test.
Install new parts.
9. Test and replace if necessary.
(Refer to Appropriate Diagnostic
Information)
10. Replace spark plugs.
DIAGNOSIS & TESTING
02
02–163Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine CONDITIONPOSSIBLE CAUSES CORRECTION
Engine Miss On Acceleration 1. Dirty or incorrectly gapped spark
plugs.
2. Contamination in fuel system.
7. Burned, warped, excessive
clearance, or pitted valves.
4. Faulty ignition coil(s).1. Clean spark plugs and set gap.
2. Clean fuel system and replace
fuel filter.
3. Replace valves.
4. Test and replace if necessary.
(Refer to Appropriate Diagnostic
Information)
Engine Miss At High Speed 1. Dirty or incorrect spark plug gap.
2. Faulty ignition coil(s).
3. Dirty fuel injector(s).
4. Contamination in fuel system.1. Clean spark plugs and set gap.
2. Test and replace if necessary.
(Refer to Appropriate Diagnostic
Information)
3. Test and replace if necessary.
(Refer to Appropriate Diagnostic
Information)
4. Clean system and replace fuel
filter.
Engine Mechanical Diagnostics
CONDITION
POSSIBLE CAUSES CORRECTION
Valve Train Noise 1. High or low oil level in crankcase.
2. Thin or diluted oil.
3. Thick oil.
4. Low oil pressure.
5. Worn cam lobe.
6. Worn valve guides.
7. Excessive runout of valve seats
on valve faces.1. Check and correct engine oil
level.
2. Change oil to correct viscosity.
3. Change engine oil and filter.
4. Check and correct engine oil
level.
5. Install new camshaft.
6. Replace cylinder head.
7. Grind valve seats and replace
valves.
Connecting Rod Noise 1. Insufficient oil supply.
2. Low oil pressure.
3. Thin or diluted oil.
4. Excessive bearing clearance.
5. Connecting rod journal out-of-
round.
6. Connecting rod out-of-round.
7. Misaligned connecting rods.
8. Connecting rod nuts loose.1. Check engine oil level.
2. Check engine oil level. Inspect oil
pump relief valve and spring.
3. Change oil to correct viscosity.
4. Measure bearings for correct
clearance. Repair if necessary.
5. Replace crankshaft or grind
surface.
6. Replace connecting rod.
7. Replace bent connecting rods.
8. Tighten the connecting rod nuts.
Main Bearing Noise 1. Insufficient oil supply.
2. Low oil pressure.
3. Thin or diluted oil.
4. Excessive bearing clearance.
5. Excessive end play.
6. Crankshaft journal out-of-round or
worn.
7. Loose flywheel or torque
converter.1. Check engine oil level.
2. Check engine oil level. Inspect oil
pump.
3. Change oil to correct viscosity.
4. Measure bearings for correct
clearance. Repair if necessary.
5. Check thrust bearing for wear on
flanges.
6. Replace crankshaft or grind
journals.
7. Tighten to correct torque.
DIAGNOSIS & TESTING
02–164Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine CONDITIONPOSSIBLE CAUSES CORRECTION
Oil Pressure Drop 1. Low oil level.
2. Faulty oil pressure sending unit.
3. Low oil pressure.
4. Clogged oil filter.
5. Thin or diluted oil.
6. Excessive bearing clearance.1. Check engine oil level.
2. Install new sending unit.
3. Check sending unit and main
bearing oil clearance.
4. Install new oil filter.
5. Change oil to correct viscosity.
6. Measure bearings for correct
clearance.
Oil Leaks 1. Misaligned or deteriorated
gaskets.
2. Loose fastener, broken or porous
metal part.
3. Misaligned or deteriorated cup or
threaded plug.1. Replace gasket.
2. Tighten, repair or replace the part.
3. Replace if necessary.
Oil Consumption Or Spark Plugs
Fouled 1. PCV system malfunction.
2. Worn, scuffed or broken rings.
3. Carbon in oil ring slots.
4. Rings fitted too tightly in grooves.
5. Worn valve guide(s).
6. Valve stem seal(s) worn or
damaged.1. Check system and repair if
necessary.
2. Hone cylinder bores. Install new
rings.
3. Install new rings.
4. Remove rings and check grooves.
If groove is not proper width, replace
piston.
5. Replace cylinder head.
6. Replace seal(s).
Cylinder Compression Pressure Test
•
The result of a cylinder compression pressure test
can be utilized to diagnose several engine malfunc-
tions.
• Ensure the battery is completely charged and the
engine starter motor is in good operating condition.
Otherwise the indicated compression pressures
may not be valid for diagnostic purposes.
Check engine oil level and add oil if neces-
sary.
Disconnect the spark plug wires.
Remove all spark plugs from engine (as spark plugs are being removed, check electrodes for
abnormal firing indicators fouled, hot, oily,
etc.).
Record cylinder number of each spark plug for future reference.
Disconnect fuel injector electrical connectors.
Be sure throttle blade is fully open during the compression check.
Insert compression pressure adaptor or the equivalent into each spark plug hole in cylinder head.
Crank engine until maximum pressure is reached on gauge. Record each cylinder pressure.
Compression should not be less than 880 kPa and not vary more than 25 percent from cylinder to cylinder.
If one or more cylinders have abnormally low compression pressures, repeat the compression test.
If the same cylinder or cylinders repeat an abnormally low reading on the second compression test, it could indicate the existence of a problem with the cylinder in question.
NOTE :
The recommended compression pressures are to be used only as a guide to diagnosing engine problems. An engine
should not be disassembled to determine the cause of low compression unless some malfunction is present.
DIAGNOSIS & TESTING
LTSM020191
02
02–165Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine 5. Using special tool CH-20013 (1), Remove the valveoil seal.
6. Remove the valve guide.
7. Remove the spark plugs.
Inspection
• Cylinder head must be flat within 0.03 mm.
• Inspect camshaft bearing journals for scoring.
• Remove carbon and varnish deposits from inside of
valve guides with a valve guide cleaner.
• Check the valve guide height.
Assembly
1. Install new valve guide if necessary.
2. Install new valve seat if necessary.
3. Using special tool MD-998774 (1), install the new
valve oil seal.
4. Install the valves into the cylinder head (larger diameter on intake side).
5. Install the valve springs.
6. Install the valve spring retainers.
CYLINDER HEAD UNIT REPAIR
LTSM020225
BESM020068 LTSM020094
02–242Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine Hard Start / Long Crank / Erratic Start / Erratic Crank
The following conditions apply to this symptom:
•The engine cranks for an extended period of time.
• The engine starts hard during a long cranking time.
1.PRELIMINARY CHECKS
• Confirm that the correct starting procedure was used by the customer before proceeding with diagnosis.
• Carry out the following preliminary checks:
Vacuum leaks
Fuel quality (concerns such as correct octane, contamination, winter/summer blend)
Intake air system (tubes)
Air cleaner (restrictions)
Battery condition and starter current draw.
Are all checks OK?
Ye s>>Go to the next step.
No
>>Repair as necessary.
Verify the symptom no longer exists.
2.CHECK ECM DTC
• With scan tool X-431, select view DTC and data stream in ECM.
Are there any DTCs present?
Ye s>>See the Diagnostic Trouble Code (DTC) List.
Go to the specific diagnostic test to troubleshoot the DTC.
No
>>Go to the next step.
3.CHECK SECONDARY IGNITION SYSTEM
• Perform the following to test the secondary ignition system:
Disconnect the injector fuse.
Remove any of the 4 spark plugs.
Connect the spark plug to spark plug wire.
Ground the spark plug on the cylinder block.
Crank the engine to test the secondary ignition system with the spark plugs removed.
Is a strong blue spark visible at each spark plug while cranking the engine?
Ye s>>Go to the next step.
No
>>Check Camshaft Position (CMP) sensor signal at ECM.
If CMP sensor is OK, check the following:
Crankshaft Position (CKP) sensor malfunction
Faulty spark plug wires
Faulty spark plugs
ELECTRONIC ENGINE CONTROLS - 2.4L ENGINE SYMPTOM DIAGNOSIS
03
03–549Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine 4.CHECK SECONDARY IGNITION SYSTEM
• Perform the following to test the secondary ignition system:
Disconnect the injector fuse.
Remove any of the 4 spark plugs.
Connect the spark plug to spark plug wire.
Ground the spark plug on the cylinder block.
Crank the engine to test the secondary ignition system with the spark plugs removed.
Is a strong blue spark visible at each spark plug while cranking the engine?
Ye s>>Go to the next step.
No
>>Check Camshaft Position (CMP) sensor signal at ECM.
If CMP sensor is OK, check the following:
Crankshaft Position (CKP) sensor malfunction
Spark plug wires
Spark plugs
5.CHECK INTAKE AIR SYSTEM
• Check for MAP/MAF sensor.
Is there any contamination?
Ye s>>Clean or replace the sensor.
No
>>Go to the next step.
6.CHECK EXHAUST SYSTEM
• Check the exhaust system for restrictions.
Is there a restriction in the exhaust system?
Ye s>>Repair as necessary.
No
>>Go to the next step.
7.CHECK BASE ENGINE CONCERNS
• Check for base engine concerns (such as improper compression, worn camshaft/valve train, gasket leaks).
Is a fault indicated?
Ye s>>Repair as necessary.
No
>>Go to the next step.
8.CHECK AUTOMATIC/MANUAL TRANSAXLE OPERATION
• Check the operation of the transaxle.
Is the transaxle operation normal?
Ye s>>Go to the next step.
No
>>Repair as necessary.
ELECTRONIC ENGINE CONTROLS - 2.4L ENGINE SYMPTOM DIAGNOSIS
03–554Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine Back Fires
The following conditions apply to this symptom:
•The engine will back fire when operated.
• The engine back fire occurs at all operating parameters.
1.PRELIMINARY CHECKS
• Carry out the following preliminary checks:
Vacuum lines (check for damage and correct routing).
Spark plug wire routing (correct firing order).
Are all checks OK?
Ye s>>Go to the next step.
No
>>Repair as necessary.
Verify the symptom no longer exists.
2.CHECK ECM DTC
• Turn the ignition switch on.
• With the scan tool X-431, select view DTC and stream data in ECM.
Are there any DTCs present?
Ye s>>See the Diagnostic Trouble Code (DTC) List.
Go to the specific diagnostic test to troubleshoot the DTC.
No
>>Go to the next step.
3.CHECK SECONDARY IGNITION SYSTEM
• Perform the following to test the secondary ignition system:
Disconnect the injector fuse.
Remove any of the 4 spark plugs.
Connect the spark plug to spark plug wire.
Ground the spark plug on the cylinder block.
Crank the engine to test the secondary ignition system with the spark plugs removed.
Is a strong blue spark visible at each spark plug while cranking the engine?
Ye s>>Go to the next step.
No
>>Check Camshaft Position (CMP) sensor signal at ECM.
If CMP sensor is OK, check the following:
Crankshaft Position (CKP) sensor malfunction
Spark plug wires
Spark plugs
4.CHECK FUEL QUALITY
• Check fuel quality (concerns such as correct octane, contamination).
Is the fuel quality OK?
Ye s>>Go to the next step.
No
>>Repair as necessary.
Verify the symptom no longer exists.
ELECTRONIC ENGINE CONTROLS - 2.4L ENGINE SYMPTOM DIAGNOSIS
03–556Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine Engine Poor Driveability
The following conditions apply to this symptom:
•Engine stalls/quits, engine runs rough, misses, buck/jerk, hesitation/stumble acceleration, surges, rolling idle.
• Engine stops unexpectedly at beginning of acceleration or during acceleration.
• Engine stops unexpectedly while cruising.
• Engine speed fluctuates during acceleration.
• Engine misses during acceleration.
• Vehicle bucks/jerks during acceleration, cruising or deceleration.
• Momentary pause during acceleration.
• Momentary minor loss in engine output.
1.PRELIMINARY CHECKS
NOTE :
Be aware of the over RPM limiting functions of the ECM.
• Carry out the following preliminary checks:
Fuel quality
Vacuum lines (check for damage and correct routing)
Intake air system (check for damaged tubes and dirty air filter)
Vehicle wiring (disconnected, corroded/damaged)
Throttle linkage.
Radiator (obstructed)
Transaxle
Are all checks OK?
Ye s>>Go to the next step.
No
>>Repair as necessary.
Verify the symptom no longer exists.
2.CHECK FOR STALL AT IDLE
• Check for engine stall at idle.
NOTE :
Confirm that proper vehicle maintenance has been performed before continuing with engine diagnosis.
• Inspect the following components:
Clean the injectors
Fuel filter
Intake air filter
Throttle body
Spark plugs
Spark plug wires
Does the engine now stall at idle?
Ye s>>Repair as necessary.
No
>>Go to the next step.
ELECTRONIC ENGINE CONTROLS - 2.4L ENGINE SYMPTOM DIAGNOSIS
03–558Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine 3.CHECK FOR ROUGH IDLE
• Check for engine rough idle.
NOTE :
Confirm that proper vehicle maintenance has been performed before continuing with engine diagnosis.
• Inspect the following components:
Clean the carbon deposit on intake and exhaust valves
Valve stem
Spark plugs
Throttle body
Spark plugs and combustion chamber
Does the engine idle rough?
Ye s>>Repair as necessary.
No
>>Go to the next step.
4.CHECK ECM DTC
• Turn the ignition switch on.
• With the scan tool X-431, read the DTC.
Are there any DTCs present?
Ye s>>Repair as necessary.
No
>>Go to the next step.
5.CHECK THE ELECTRONIC THROTTLE CONTROL (ETC) ACTUATOR
• Start engine and let idle.
• While checking for RPM drop or engine stall, disconnect ETC actuator connector.
Did RPM drop or engine stall when the ETC connector was disconnected?
Ye s>>Connect ETC actuator connector.
Go to the next step.
No
>>Repair as necessary.
ELECTRONIC ENGINE CONTROLS - 2.4L ENGINE SYMPTOM DIAGNOSIS
03
03–559Chery Automobile Co., Ltd.

Downloaded from www.Manualslib.com manuals search engine 6.CHECK SECONDARY IGNITION SYSTEM
• Perform the following to test the secondary ignition system:
Disconnect the injector fuse.
Remove any of the 4 spark plugs.
Connect the spark plug to spark plug wire.
Ground the spark plug on the cylinder block.
Crank the engine to test the secondary ignition system with the spark plugs removed.
Is a strong blue spark visible at each spark plug while cranking the engine?
Ye s>>Go to the next step.
No
>>Check Camshaft Position (CMP) sensor signal at ECM.
If CMP sensor is OK, check the following:
Crankshaft Position (CKP) sensor malfunction
Spark plug wires
Spark plugs
7.CHECK FUEL SYSTEM PRESSURE
• Release the fuel system pressure (See Fuel Pressure Relief Procedure in Section 04 Fuel Delivery).
• Check fuel system pressure (See Fuel Pressure Test in Section 04 Fuel Delivery).
Is fuel pressure correct?
Ye s>>Go to the next step.
No
>>If the fuel pressure is greater than 400 kPa (4.0 bar):
Replace the fuel pressure regulator.
If the fuel pressure is less than 400 kPa (4.0 bar):
Check the fuel supply system for restrictions or leaks.
If no problems, repair or replace fuel filter, pressure regulator or fuel pump assembly.
8.CHECK EXHAUST SYSTEM
• Check the exhaust system for restrictions.
Is there a restriction in the exhaust system?
Ye s>>Repair as necessary.
No
>>Go to the next step.
9.CHECK PCV SYSTEM
• Check the Positive Crankcase Ventilation (PCV) system.
• Remove PCV valve and shake it.
Is PCV valve normal?
Ye s>>Go to the next step.
No
>>Replace the PCV valve.
ELECTRONIC ENGINE CONTROLS - 2.4L ENGINE SYMPTOM DIAGNOSIS
03–560Chery Automobile Co., Ltd.