Engine Mechanical - 5.3L: Diagnosis GMC Envoy II

Diagnostic Starting Point - Engine Mechanical

Begin the system diagnosis by reviewing the Disassembled Views , Engine Component Description , Lubrication Description (Main Pressure Below 55 psi - DOD Off) or Lubrication Description (Main Pressure Above 55 psi - DOD Off) or Lubrication Description (Main Pressure Below 55 psi - DOD On) or Lubrication Description (Main Pressure Above 55 psi - DOD On) and Displacement on Demand (DOD) System Description in Engine Controls. Reviewing the description and operation information will help you determine the correct symptom diagnostic procedure when a malfunction exists. Reviewing the description and operation information will also help you determine if the condition described by the customer is normal operation. Refer to Symptoms - Engine Mechanical in order to identify the correct procedure for diagnosing the system and where the procedure is located.

Strategy Based Diagnostics

1. Perform a «Diagnostic System Check - Vehicle»(ref-200355-S37572612702005102000000) in Vehicle DTC Information before using the symptom tables.
2. Review the system operations in order to familiarize yourself with the system functions. Refer to «Disassembled Views»(ref-200397-S06222515552005102000000) , «Engine Component Description»(ref-200397-S24969781032005102000000) , «Lubrication Description (Main Pressure Below 55 psi - DOD Off)»(ref-200397-S12108297862005102000000) or «Lubrication Description (Main Pressure Above 55 psi - DOD Off)»(ref-200397-S36558892122005102000000) or «Lubrication Description (Main Pressure Below 55 psi - DOD On)»(ref-200397-S18396987412005102000000) or «Lubrication Description (Main Pressure Above 55 psi - DOD On)»(ref-200397-S41279860062005102000000) , «Displacement on Demand (DOD) System Description»(ref-200373-S04714752132005102000000) in Engine Controls and «Drive Belt System Description»(ref-200397-S00007953452005102000000) .

All diagnosis on a vehicle should follow a logical process. Strategy based diagnostics is a uniform approach for repairing all systems. The diagnostic flow may always be used in order to resolve a system condition. The diagnostic flow is the place to start when repairs are necessary. For a detailed explanation, refer to Strategy Based Diagnosis in General Information.

Visual/Physical Inspection

1. Inspect for aftermarket devices which could affect the operation of the Engine. Refer to «Checking Aftermarket Accessories»(ref-200357-S14022145092005102000000) in Wiring Systems.
2. Inspect the easily accessible or visible system components for obvious damage or conditions which could cause the symptom.
3. Check for the correct oil level, proper oil viscosity, and correct filter application.
4. Verify the exact operating conditions under which the concern exists. Note factors such as engine RPM, ambient temperature, engine temperature, amount of engine warm-up time, and other specifics.
5. Compare the engine sounds, if applicable, to a known good engine and make sure you are not trying to correct a normal condition.

Symptom List

Refer to a symptom diagnostic procedure from the following list in order to diagnose the symptom

1. «Base Engine Misfire without Internal Engine Noises»(ref-200397-S26860054002005102000000)
2. «Base Engine Misfire with Abnormal Internal Lower Engine Noises»(ref-200397-S05739791942005102000000)
3. «Base Engine Misfire with Abnormal Valve Train Noise»(ref-200397-S03687686482005102000000)
4. «Base Engine Misfire with Coolant Consumption»(ref-200397-S00220936592005102000000)
5. «Base Engine Misfire with Excessive Oil Consumption»(ref-200397-S20630627142005102000000)
6. «Engine Noise on Start-Up, but Only Lasting a Few Seconds»(ref-200397-S37193861072005102000000)
7. «Upper Engine Noise, Regardless of Engine Speed»(ref-200397-S14181503652005102000000)
8. «Lower Engine Noise, Regardless of Engine Speed»(ref-200397-S29855333482005102000000)
9. «Engine Noise Under Load»(ref-200397-S08086186492005102000000)
10. «Engine Will Not Crank - Crankshaft Will Not Rotate»(ref-200397-S02284088162005102000000)
11. «Coolant in Combustion Chamber»(ref-200397-S26389332182005102000000)
12. «Coolant in Engine Oil»(ref-200397-S24978955082005102000000)
13. «Displacement on Demand (DOD) System Diagnosis»(ref-200397-S14259151362005102000000)
14. «Engine Compression Test»(ref-200397-S09606859772005102000000)
15. «Displacement on Demand (DOD) System Compression Test»(ref-200397-S03171460102005102000000)
16. «Cylinder Leakage Test»(ref-200397-S14180289712005102000000)
17. «Oil Consumption Diagnosis»(ref-200397-S31267005372005102000000)
18. «Oil Pressure Diagnosis and Testing»(ref-200397-S39760760942005102000000)
19. «Displacement on Demand (DOD) Oil Pressure Relief Valve Diagnosis and Testing»(ref-200397-S11960425202005102000000)
20. «Displacement on Demand (DOD) Valve Lifter Oil Manifold Diagnosis and Testing»(ref-200397-S19322440702005102000000)
21. «Oil Leak Diagnosis»(ref-200397-S06502675032005102000000)
22. «Drive Belt Chirping Diagnosis»(ref-200397-S22302915662005102000000)
23. «Drive Belt Squeal Diagnosis»(ref-200397-S13563459102005102000000)
24. «Drive Belt Whine Diagnosis»(ref-200397-S07126544622005102000000)
25. «Drive Belt Rumbling Diagnosis»(ref-200397-S30147577042005102000000)
26. «Drive Belt Vibration Diagnosis»(ref-200397-S14945589542005102000000)
27. «Drive Belt Falls Off Diagnosis»(ref-200397-S12739718842005102000000)
28. «Drive Belt Excessive Wear Diagnosis»(ref-200397-S32915219642005102000000)
29. «Drive Belt Tensioner Diagnosis»(ref-200397-S20608460772005102000000)

Displacement on Demand (DOD) System Diagnosis

1. Check the engine oil level. Fill as required.
2. Using the scan tool, check for diagnostic codes within the engine control module (ECM). Refer to «Diagnostic System Check - Vehicle»(ref-200355-S37572612702005102000000) in Vehicle DTC Information. Repair as required.
3. Verify proper engine oil pressure and operation of the Displacement-on-Demand (DOD) oil pressure relief valve. Refer to «Oil Pressure Diagnosis and Testing»(ref-200397-S39760760942005102000000) .
4. Verify proper operation of the DOD system components. Refer to «Displacement on Demand (DOD) System Compression Test»(ref-200397-S03171460102005102000000) .
5. Remove the valve lifter oil manifold (VLOM). Refer to «Valve Lifter Oil Manifold Replacement»(ref-200397-S27332754812005102000000) .
6. Verify proper operation of the VLOM. Refer to «Displacement on Demand (DOD) Valve Lifter Oil Manifold Diagnosis and Testing»(ref-200397-S19322440702005102000000) .
7. Replace the DOD valve lifters as required. Both intake and exhaust lifters should be replaced in pairs. Refer to «Valve Lifter Replacement»(ref-200397-S34439083192005102000000) .

Engine Compression Test

1. Charge the battery if the battery is not fully charged.
2. Disable the ignition system.
3. Disable the fuel injection system.
4. Remove all spark plugs.
5. Turn the ignition to the ON position.
6. Depress the accelerator pedal to position the throttle plate wide open.
7. Start with the compression gage at zero and crank the engine through four compression strokes, four puffs.
8. Check the compression for each cylinder. Record the readings.
9. If a cylinder has low compression, inject approximately 15 ml (1 tablespoon) of engine oil into the combustion chamber through the spark plug hole. Check the compression again and record the reading.
10. The minimum compression in any one cylinder should not be less than 70 percent of the highest cylinder. No cylinder should read less than 690 kPa (100 psi). For example, if the highest pressure in any one cylinder is 1 035 kPa (150 psi), the lowest allowable pressure for any other cylinder would be 725 kPa (105 psi). (1 035 x 70% = 725) (150 x 70% = 105). Normal - Compression builds up quickly and evenly to the specified compression for each cylinder. Piston Rings Leaking - Compression is low on the first stroke. Compression builds up with the following strokes, but does not reach normal. Compression improves considerably when you add oil. Valves Leaking - Compression is low on the first stroke. Compression usually does not build up on the following strokes. Compression does not improve much when you add oil. If two adjacent cylinders have lower than normal compression, and injecting oil into the cylinders does not increase the compression, the cause may be a head gasket leaking between the cylinders.

Displacement on Demand (DOD) System Compression Test

The Displacement-on-Demand (DOD) system compression test is a functional test of the valve lifter oil manifold (VLOM) and valve lifters. Using a compression gage, the technician can monitor the specific cylinders ability to go into and out of DOD as commanded by the scan tool. The actual pressure values on the compression gage are not as critical as is observing the on-off switching action of the solenoid and valve lifters.

1. Check the engine oil level. Fill as required.
2. Perform the Diagnostic System Check. Refer to «Diagnostic System Check - Vehicle»(ref-200355-S37572612702005102000000) in Vehicle DTC Information.
3. Disable the ignition system for the cylinder to be tested, by disconnecting the electrical wire harness to the ignition coil.
4. Disable the fuel injection system for the cylinder to be tested, by disconnecting the electrical wire harness to the fuel injector.
5. Remove the spark plug and wire for the cylinder to be tested.
6. Install a 0-1378 kPa (0-200 psi) compression gage.
7. Start the engine.
8. Using the scan tool output controls, command the solenoid ON, for the cylinder to be deactivated.
9. Depress the Schrader valve on the compression gage in order to release the pressure and zero the gage. With the engine running and the cylinder in DOD mode, the compression reading should be less than 172 kPa (25 psi).
10. Using the scan tool, de-energize the solenoid while observing the reading on the compression gage. With the engine running and the cylinder NOT in DOD mode, the compression gage reading should increase quickly to greater than 345 kPa (50 psi).
11. Test each of the four DOD cylinders one at a time. If the readings are not within specifications, remove and test the VLOM as required. Refer to «Valve Lifter Oil Manifold Replacement»(ref-200397-S27332754812005102000000) and «Displacement on Demand (DOD) Valve Lifter Oil Manifold Diagnosis and Testing»(ref-200397-S19322440702005102000000) .
12. If the compression test has been performed and all DOD cylinders are operating within specifications, the DOD system is performing as designed and no repairs are required.
13. Clear the DTCs with a scan tool.

Oil Consumption Diagnosis

Oil Consumption Diagnosis

Oil Pressure Diagnosis and Testing

Tools Required

1. J 21867 Pressure Gage
2. J 42907 Oil Pressure Tester

1. With the vehicle on a level surface, run the vehicle for a few minutes, allow adequate drain down time, 2-3 minutes, and measure the oil level.
2. If required, add the recommended grade engine oil and fill the crankcase until the oil level measures full on the oil level indicator.
3. Run the engine briefly, 10-15 seconds, and verify low or no oil pressure on the vehicle gage or light.
4. Listen for a noisy valve train or a knocking noise.
5. Inspect for the following conditions: Oil diluted by water or glycol anti freeze Refer to «Coolant in Engine Oil»(ref-200397-S24978955082005102000000) . Foamy oil, which may be caused by a cut or damaged oil pump screen O-ring seal
6. Remove the oil filter and install the J 42907 .
7. Install J 21867 or equivalent to the J 42907 .
8. Run the engine and measure the engine oil pressure.
9. Compare the readings to «Engine Mechanical Specifications»(ref-200397-S27357677232005102000000) .
10. If the engine oil pressure is below specifications, inspect the engine for one or more of the following conditions: Oil pump worn or dirty Refer to «Oil Pump Cleaning and Inspection»(ref-200397-S18552134552005102000000) . Oil pump-to-engine block bolts loose Refer to «Oil Pump, Pump Screen and Deflector Installation»(ref-200397-S33538803462005102000000) . Oil pump screen loose, plugged, or damaged Oil pump screen O-ring seal missing or damaged Oil filter tube loose or a leaking or damaged gasket Malfunctioning oil pump pressure relief valve Excessive bearing clearance Cracked, porous, or restricted oil galleries Oil gallery plugs missing or incorrectly installed Refer to «Engine Block Plug Installation»(ref-200397-S30842422912005102000000) . Improper operation of the Displacement on Demand (DOD) oil pressure relief valve Refer to «Displacement on Demand (DOD) Oil Pressure Relief Valve Diagnosis and Testing»(ref-200397-S11960425202005102000000) .

Displacement on Demand (DOD) Oil Pressure Relief Valve Diagnosis and Testing

Tools Required

1. J 21867 Pressure Gage
2. J-21867-16 Oil Pressure Adapter. See «Special Tools»(ref-200397-S12228589952005102000000) .
3. J 42907 Oil Pressure Tester

1. Remove the oil filter and install the J 42907 .
2. Install the J 21867 or equivalent to the J 42907 .
3. Remove the oil pressure sensor and install the J-21867-16 . See «Special Tools»(ref-200397-S12228589952005102000000) .
4. Install the J 21867 (1), or equivalent, to the J-21867-16 (2). See «Special Tools»(ref-200397-S12228589952005102000000) .
5. Run the engine and measure the engine oil pressure while observing both gages. Operate the throttle as required to increase and decrease the engine oil pressure. With the engine running and the lower pressure gage (2) measuring below 379 kPa (55 psi), both gages should display the same pressure reading. If the readings are not the same and the lower gage (2) has a higher reading, the DOD oil pressure relief valve is stuck in the open position or the valve lifter oil manifold filter is plugged. With the engine running and the lower pressure gage (2) measuring above 379 kPa (55 psi), the upper gage (1) should display no greater than 379-517 kPa (55-75 psi). If the reading on the upper gage (1) is greater than 517 kPa (75 psi), the DOD oil pressure relief valve is stuck in the closed position.
6. Repair as required.

Displacement on Demand (DOD) Valve Lifter Oil Manifold Diagnosis and Testing

Tools Required

1. EN-46999 Displacement-on-Demand Tester. See «Special Tools»(ref-200397-S12228589952005102000000) .
2. EN-46999-1 Displacement-on-Demand Tester Air Adapter. See «Special Tools»(ref-200397-S12228589952005102000000) .
3. EN-46999-5 Displacement-on-Demand Tester Harness - Small Block V8. See «Special Tools»(ref-200397-S12228589952005102000000) .

Scheme 71

The manifold bench test provides a maximum 206 kPa (30 psi) of filtered shop air to the manifold and will test each solenoid/valve for the following conditions

1. Proper operation
2. A stuck open condition - constant air flow
3. A stuck closed condition - no air flow
4. A flow restriction within the manifold

1. Individually depress each of the buttons 1-4 on the EN-46999 in order to activate each of the solenoid/valves. See «Special Tools»(ref-200397-S12228589952005102000000) . When activating each solenoid/valve, a loud click should be heard from the solenoid and an increased amount of air will exit the outlet ports. Button 1 will energize the solenoid/valve 1 for engine cylinder number 1. Button 2 will energize the solenoid/valve 2 for engine cylinder number 4. Button 3 will energize the solenoid/valve 3 for engine cylinder number 6. Button 4 will energize the solenoid/valve 4 for engine cylinder number 7.
2. Do not lift the manifold assembly by the electrical lead frame.
3. Install the EN-46999-1 (1) to the manifold. See «Special Tools»(ref-200397-S12228589952005102000000) .
4. Install 2 of the manifold bolts (2) to the EN-46999-1 . See «Special Tools»(ref-200397-S12228589952005102000000) . Tighten: Tighten the bolts to 25 N.m (18 lb ft).
5. Connect the air out hose (2) of the EN-46999 (5) to the EN-46999-1 (1). See «Special Tools»(ref-200397-S12228589952005102000000) . Verify the air supply switch (4) is in the off position.
6. Connect the air in hose (6) of the EN-46999 (5) to a shop air source. See «Special Tools»(ref-200397-S12228589952005102000000) .
7. Connect the 12 volt power supply connectors (7) of the EN-46999 (5) to a 12 volt power supply. See «Special Tools»(ref-200397-S12228589952005102000000) . Verify the Power light (8) on the tool is illuminated. If the light on the tool is not illuminated when connected to a 12 volt power supply, test and/or replace the 3 amp fuse.
8. Connect the EN-46999-5 power cable (3) to the electrical connector of the manifold. See «Special Tools»(ref-200397-S12228589952005102000000) .
9. Turn the air supply switch of the EN-46999 to the ON position. See «Special Tools»(ref-200397-S12228589952005102000000) . With the air supply connected to the manifold assembly and the solenoid/valves in the closed position, a limited amount of air will exit each of the bleed holes (3) and outlet ports (1, 2) of the manifold.
10. Position the manifold assembly onto a bench at a 45 degree angle in order to test solenoid/valves 1 and 4.
11. Depress button number 1 on the tool to activate solenoid/valve 1. With button 1 depressed, the solenoid/valve (1) should open, allowing an increased amount of air to exit the outlet ports (2) of the manifold.
12. Depress button number 4 on the tool to activate solenoid/valve 4. With button 4 depressed, the solenoid/valve (4) should open, allowing an increased amount of air to exit the outlet ports (3) of the manifold.
13. Reposition the manifold assembly onto a bench at a 45 degree angle in order to test solenoid/valves 2 and 3.
14. Depress button number 2 on the tool to activate solenoid/valve 2. With button 2 depressed, the solenoid/valve (2) should open, allowing an increased amount of air to exit the outlet ports (4) of the manifold.
15. Depress button number 3 on the tool to activate solenoid/valve 3. With button 3 depressed, the solenoid/valve (3) should open, allowing an increased amount of air to exit the outlet ports (1) of the manifold.
16. When the test is completed, turn the air source switch on the EN-46999 to the off position and disconnect the tool from the 12 volt power supply, shop air source and manifold assembly. See «Special Tools»(ref-200397-S12228589952005102000000) .
17. If after testing, it has been determined that one or more of the solenoid/valves is not functioning properly, replace the manifold as an assembly.
18. If after testing, it has been determined that the solenoid/valves are functioning properly, replace the valve lifters as required. Both intake and exhaust lifters should be replaced in pairs.

Oil Leak Diagnosis

Oil Leak Diagnosis

Crankcase Ventilation System Inspection/Diagnosis

Crankcase Ventilation System Inspection/Diagnosis

Diagnostic Aids

The chirping noise may be intermittent due to moisture on the drive belts or the accessory drive pulleys. In order to duplicate the customer's concern, it may be necessary to spray a small amount of water onto the drive belts. If spraying water onto the drive belts duplicates the symptom, cleaning the accessory drive pulleys may be the most probable solution.

A loose or improper installation of a body or suspension component, or other items on the vehicle may also cause the chirping noise.

A loose or improper installation of a body, or suspension component, or other items on the vehicle may cause the squeal noise.

If the squeal is intermittent, verify that it is not the accessory drive components by varying their loads, making sure they are operating to their maximum capacity. An overcharged air conditioning (A/C) system, a power steering system restriction or the incorrect fluid, or a failing generator are suggested items to inspect.

The drive belts will not cause the whine.

If the whine is intermittent, verify that it is not the accessory drive components by varying their loads, making sure they are operating to their maximum capacity. An overcharged air conditioning (A/C) system, a power steering system restriction or the incorrect fluid, or a failing generator are suggested items to inspect.

Vibration from the engine operating may cause a body component or another part of the vehicle to make rumbling noise.

The drive belts may have a condition that can not be seen or felt. Sometimes replacing the drive belts may be the only repair for the symptom.

If after replacing the drive belts and completing the diagnostic table, the rumbling is only heard with the drive belts installed, there might be an accessory drive component failure. Varying the load on the accessory drive components may aid in identifying which component is causing the rumbling noise.

The accessory drive components may have an affect on engine vibration. An overcharged air conditioning (A/C) system, a power steering system restriction, or the incorrect fluid, or an extra load placed on the generator are suggested items to inspect. To help identify an intermittent or an improper condition, vary the loads on the accessory drive components.

If the drive belts repeatedly falls off the accessory drive pulleys, this may be caused by a pulley misalignment.

An extra load that is quickly applied or released by an accessory drive component may also cause the drive belts to fall off. Verify that the accessory drive components are operating properly.

If the drive belts is the incorrect length, the drive belt tensioner may not maintain the proper tension on the drive belts.

Excessive wear on a drive belts is usually caused by incorrect installation or the incorrect drive belts for the application.

Minor misalignment of the accessory drive pulleys will not cause excessive wear, but will probably cause the drive belts to make a noise or fall off.

Excessive misalignment of the accessory drive pulleys will cause excessive wear and may also make the drive belts fall off.

Inspection Procedure

1. Remove the drive belt. Refer to «Drive Belt Replacement - Accessory»(ref-200397-S04105284972005102000000) or to «Drive Belt Replacement - Air Conditioning»(ref-200397-S08784724632005102000000) .
2. Move the drive belt tensioner through its full travel. The movement should feel smooth. There should be no binding. The tensioner should return freely.
3. If any binding is observed, replace the drive belt tensioner. Refer to «Drive Belt Tensioner Replacement - Accessory»(ref-200397-S18653146752005102000000) or to «Drive Belt Tensioner Replacement - Air Conditioning»(ref-200397-S11988456412005102000000) .
4. Install the drive belt. Refer to «Drive Belt Replacement - Accessory»(ref-200397-S04105284972005102000000) or to «Drive Belt Replacement - Air Conditioning»(ref-200397-S08784724632005102000000) .

Engine Block Cleaning and Inspection

Tools Required

1. J 8087 Cylinder Bore Gage
2. J 42385-100 Head/Main Bolt Thread Repair Kit. See «Special Tools»(ref-200397-S12228589952005102000000) .

1. Inspect the following components: Cylinder walls for excessive scratches, gouging, or ring ridge Cylinder bores for excessive ring ridge at the top of the cylinder Coolant jacket for cracks Valve lifter bores for excessive scoring or wear Crankshaft bearing webs for cracks Gasket sealing surfaces for excessive scratches or gouging Refer to «Replacing Engine Gaskets»(ref-200397-S39543702712005102000000) . Oil galleries for restrictions Threaded bolt holes for damaged threads Scoring or damage to the displacement on demand oil passages or sealing surfaces
2. Measure the cylinder bores for excessive ring ridge at the top of the cylinder.

Crankshaft and Bearings Cleaning and Inspection

Tools Required

1. J 7872 Magnetic Base Dial Indicator Set
2. J 43690 Rod Bearing Checking Tool. See «Special Tools»(ref-200397-S12228589952005102000000) .
3. J 43690-100 Rod Bearing Checking Tool - Adapter Kit. See «Special Tools»(ref-200397-S12228589952005102000000) .

1. Perform a visual inspection of the crankshaft for damage.
2. Inspect the CKP reluctor ring teeth (1) for damage.
3. Inspect the crankshaft journals for wear (1). Journals should be smooth with no signs of scoring, wear, or damage.
4. Inspect the crankshaft journals for grooves or scoring (2).
5. Inspect the crankshaft journals for scratches or wear (3).
6. Inspect the crankshaft journals for pitting or imbedded bearing material (4).
7. Inspect the crankshaft rear oil seal surface (5) for grooves or scoring.
8. Inspect the crankshaft key (122), keyway (1), and threaded hole (2) for damage.
9. Measure the crank pins for the out-of-round.
10. Measure the crank pins for taper.
11. Measure the crankshaft thrust wall width. A crankshaft with a thrust wall width in excess of 26.2 mm (1.0315 in) (a) must be replaced.
12. Measure the crankshaft runout. Use wooden V blocks or a fixture to support the crankshaft on the front and rear journals.
13. Use the J 7872 in order to measure the crankshaft runout at the front and rear intermediate journals.
14. Use the J 7872 in order to measure the runout of the crankshaft rear flange.
15. Use the J 7872 in order to measure the runout of the crankshaft position reluctor ring. Reluctor ring runout should be measured 1.0 mm (0.04 in) below the ring teeth. If the reluctor ring has runout in excess of 0.7 mm (0.028 in), replace the crankshaft.
16. Inspect crankshaft bearings for craters or pockets. Flattened sections on the bearing halves also indicate fatigue.
17. Inspect the crankshaft bearings for excessive scoring or discoloration.
18. Inspect the crankshaft bearings for dirt or debris imbedded into the bearing material.
19. Inspect the crankshaft bearings for improper seating indicated by bright, polished sections of the bearing. If the lower half of the bearing is worn or damaged, both upper and lower halves should be replaced. Generally, if the lower half is suitable for use, the upper half should also be suitable for use.

Crankshaft Balancer Cleaning and Inspection

1. Clean the crankshaft balancer in solvent.
2. Clean the belt grooves of all dirt or debris with a wire brush.
3. Dry the crankshaft balancer with compressed air.
4. Inspect the crankshaft balancer for the following conditions: Worn, grooved, or damaged hub seal surface A crankshaft balancer hub seal surface with excessive scoring, grooves, rust or other damage must be replaced. Minor imperfections on the hub seal surface may be removed with polishing compound or fine grade emery cloth. IMPORTANT: In order for the belt to track properly, the belt grooves should be free of all dirt or debris. Dirty or damaged belt grooves The balancer belt grooves should be free of any nicks, gouges, or other damage that may not allow the belt to track properly. Minor imperfections may be removed with a fine file. Worn, chunking, or deteriorated rubber between the hub and pulley

Engine Flywheel Cleaning and Inspection

1. Clean the flywheel in solvent.
2. Dry the flywheel with compressed air.
3. Inspect the flywheel for the following conditions: Damaged ring gear teeth Stress cracks around the flywheel-to-crankshaft bolt hole locations IMPORTANT: Do not attempt to repair the welded areas that retain the ring gear to the flywheel plate. Install a new flywheel. Welded areas that retain the ring gear onto the flywheel for cracking

Camshaft and Bearings Cleaning and Inspection

Tools Required

1. J 7872 Magnetic Base Dial Indicator Set
2. J 8520 Camshaft Lobe Lift Indicator. See «Special Tools»(ref-200397-S12228589952005102000000) .

1. Clean the components in solvent.
2. Dry the components with compressed air.
3. Inspect the camshaft bearing journals (1) for scoring or excessive wear.
4. Inspect the camshaft valve lifter lobes (2) for scoring or excessive wear.
5. Inspect the threaded bolt holes (3) in the front of the camshaft for damaged threads or debris.
6. Inspect the camshaft sprocket pin (204) for damage.
7. Inspect the camshaft retainer plate (203) for wear or a damaged sealing gasket. If the camshaft retainer plate sealing gasket is not cut or damaged, it may be used again.
8. Inspect the camshaft bearings for proper fit in the engine block. Camshaft bearings have an interference fit to the engine block and should not be loose in their engine block bearing bores.
9. Inspect the camshaft bearings for excessive wear or scoring. Bearings with excessive scoring or wear must be replaced.
10. Measure the camshaft journals for wear and out-of-round with a micrometer. If the camshaft bearing journals measure greater than 0.025 mm (0.001 in) out-of-round, replace the camshaft. If the camshaft bearing journal diameter measures less than 54.99 mm (2.164 in), replace the camshaft.
11. Using a micrometer, measure the camshaft lobes for wear. Refer to «Engine Mechanical Specifications»(ref-200397-S27357677232005102000000) .
12. Measure the camshaft runout. Mount the camshaft in wooden V blocks or between centers on a fixture. Using the J 7872 , measure the runout of the intermediate camshaft bearing journals. If camshaft runout exceeds 0.05 mm (0.002 in), the camshaft is bent and should be replaced.

Timing Chain and Sprockets Cleaning and Inspection

1. Clean the components with cleaning solvent.
2. Dry the components with compressed air.
3. Inspect the timing chain (1) for binding or wear.
4. Inspect the camshaft position (CMP) sensor raised area (2) for nicks or damage.
5. Inspect for worn, damaged, or chipped teeth (3).
6. Inspect for a damaged keyway (4).
7. Inspect for worn oil pump drive splines (5).

Valve Rocker Arm and Push Rods Cleaning and Inspection

1. Mark, sort, or organize the components for assembly. Refer to «Separating Parts»(ref-200397-S15772230512005102000000) .
2. Clean the components with cleaning solvent.
3. Dry the components with compressed air.
4. Inspect the valve rocker arms bearings (2) for binding or roughness.
5. Inspect the valve rocker arm pushrod sockets (3) and valve stem mating surfaces (1). These surfaces should be smooth with no scoring or exceptional wear.
6. Inspect the pushrods for worn or scored ends. These surfaces should be smooth with no scoring or exceptional wear.
7. Inspect the pushrods for bends. Roll the pushrod on a flat surface to determine if the pushrod is bent.
8. Inspect the pushrod oil passages for restrictions.
9. Inspect the rocker arm pivot supports for cracks, wear, or other damage.

Cylinder Head Cleaning and Inspection

Tools Required

1. J 8089 Carbon Removal Brush. See «Special Tools»(ref-200397-S12228589952005102000000) .
2. J 9666 Valve Spring Tester. See «Special Tools»(ref-200397-S12228589952005102000000) .

1. Clean the following components: Use the J 8089 in order to remove the carbon from the combustion chambers. See «Special Tools»(ref-200397-S12228589952005102000000) . Gasket surfaces Refer to «Replacing Engine Gaskets»(ref-200397-S39543702712005102000000) . Valve stems and heads on a buffing wheel Bolt hole threads Remove all dirt, debris, or threadlocking material from the bolt holes.
2. Inspect the cylinder head for the following conditions: Cracks in the exhaust ports and combustion chambers External cracks in the water chambers Gasket surfaces for excessive scratches or gouging Refer to «Replacing Engine Gaskets»(ref-200397-S39543702712005102000000) . Bolt hole threads for debris or damaged threads Refer to «Thread Repair»(ref-200397-S16458760272005102000000) or «Thread Repair Specifications»(ref-200397-S10831468052005102000000) .
3. Inspect the cylinder head for warpage. Refer to «Engine Mechanical Specifications»(ref-200397-S27357677232005102000000) .
4. Use the J 9666 in order to measure the valve spring tension. See «Special Tools»(ref-200397-S12228589952005102000000) . Refer to «Engine Mechanical Specifications»(ref-200397-S27357677232005102000000) .

Oil Pump Cleaning and Inspection

1. Clean the parts in solvent.
2. Dry the parts with compressed air.
3. Inspect the oil pump housing (413) and the cover (409) for cracks, excessive wear, scoring, or casting imperfections.
4. Inspect the oil pump housing-to-engine block oil gallery surface for scratches or gouging.
5. Inspect the oil pump housing for damaged bolt hole threads.
6. Inspect the relief valve plug (416) and plug bore for damaged threads.
7. Inspect the oil pump internal oil passages for restrictions.
8. Inspect the drive gear (410) and driven gear (412) for chipping, galling or wear. Minor burrs or imperfections on the gears may be removed with a fine oil stone.
9. Inspect the drive gear splines for excessive wear.
10. Inspect the pressure relief valve (414) and bore for scoring or wear. The valve must move freely in the bore with no restrictions.
11. Inspect the oil pump screen (407) for debris or restrictions.
12. Inspect the oil pump screen for broken or loose wire mesh.

Engine Front Cover Cleaning and Inspection

1. Remove the crankshaft oil seal (140) from the front cover.
2. Clean the cover in solvent. Remove the sealant from the cover oil pan surface. Refer to «Replacing Engine Gaskets»(ref-200397-S39543702712005102000000) .
3. Dry the cover with compressed air.
4. Inspect the gasket sealing surfaces for excessive scratches or gouging.
5. Inspect the threaded bolt holes for damaged threads or debris.
6. Inspect the crankshaft oil seal and camshaft position (CMP) sensor mounting bores for damage.

Engine Rear Cover Cleaning and Inspection

1. Remove the crankshaft oil seal (141) from the rear cover.
2. Clean the cover in solvent. Remove the sealant from the cover oil pan surface. Refer to «Replacing Engine Gaskets»(ref-200397-S39543702712005102000000) .
3. Dry the cover with compressed air.
4. Inspect the gasket sealing surfaces for excessive scratches or gouging.
5. Inspect the cover-to-oil pan threaded bolt holes for damaged threads or debris.
6. Inspect the crankshaft oil seal mounting bore for damage.

Valve Lifter Oil Manifold Cleaning and Inspection

1. Do not lift the manifold assembly by the electrical lead frame.
2. Remove the oil pressure sensor (706) and washer (707).
3. Remove the oil screen (452) with O-ring (454).
4. Clean the manifold with compressed air.
5. Inspect for loose electrical solenoids (1-4) or loose or missing bolts.
6. Inspect for damage to the electrical lead frame (5).
7. Inspect for a damaged electrical connector, for bent or corroded pins.
8. Inspect for damaged interior sealing gaskets (1-8). If the interior sealing gaskets are damaged, the manifold must be replaced as an assembly.
9. Inspect for a damaged exterior sealing gasket (9) or scored gasket surfaces.
10. Inspect for debris or restrictions within the oil passages of the manifold. Refer to «Displacement on Demand (DOD) Valve Lifter Oil Manifold Diagnosis and Testing»(ref-200397-S19322440702005102000000) .

Valve Rocker Arm Cover Cleaning and Inspection

1. Inspect the oil fill tube (423) for a loose fit or damage.
2. Inspect the covers for the following conditions: Scoring or damage to the gasket surfaces Ventilation system passages for restrictions Threaded bolt holes for damage or debris

Oil Pan Cleaning and Inspection

1. Remove the oil filter tube bolts (435, 446) and gaskets (445, 448).
2. Remove the oil filter tube (447).
3. Remove the plugs (449) from the oil galleries.
4. Remove the oil pan baffle and bolts.
5. Remove the oil filter fitting and oil filter bypass valve as required. Refer to «Oil Filter and Adapter Removal»(ref-200397-S19666798262005102000000) .
6. Clean the oil pan in solvent. Be sure to thoroughly clean all of the oil passages and recesses of the pan.
7. Dry the oil pan with compressed air.
8. Inspect the oil pan for the following conditions: Damaged gasket surfaces Restrictions within the oil passages of the pan Threaded bolt holes for damage
9. Inspect the oil filter tube for restrictions or damaged gasket surfaces.
10. Inspect the displacement on demand oil pressure relief valve for proper operation. Lightly depress the valve (2). The valve spring (1) should seat the valve to the proper closed position.
11. The relief valve (455) is press-fit into the oil filter tube and is serviceable separately.

1. Inspect the manifold for the following conditions: Damaged gasket or sealing surfaces Loose threaded inserts or studs Debris or restrictions within the passages of the manifold Damaged or broken vacuum fittings Inspect the composite intake manifold assembly for cracks or other damage.
2. Inspect the intake manifold cylinder head deck for warpage. Locate a straight edge across the intake manifold cylinder head deck surface. Position the straight edge across a minimum of two runner port openings. Insert a feeler gage between the intake manifold and the straight edge. An intake manifold with warpage in excess of 3 mm (0.118 in) over a 200 mm (7.87 in) area is warped and should be replaced.

Exhaust Manifold Cleaning and Inspection

1. Clean the exhaust manifold (600) and heat shield (603) in solvent.
2. Dry the exhaust manifold with compressed air.
3. Inspect the exhaust manifold-to-cylinder head gasket surface for excessive scratches or gouging.
4. Inspect for a loose, damaged, or cracked heat shield (603).
5. Inspect the studs (605) for damaged threads.
6. Use a straight edge and a feeler gage and measure the exhaust manifold cylinder head deck for warpage. An exhaust manifold deck with warpage in excess of 0.25 mm (0.01 in) within the two front or two rear runners or 0.5 mm (0.02 in) overall, may cause an exhaust leak and may effect OBD II system performance. Exhaust manifolds not within specifications must be replaced.

Coolant Air Bleed Pipe Cleaning and Inspection

1. Remove the seals (308) from the pipe (307) and covers.
2. Clean the pipe and covers in solvent.
3. Dry the pipe and covers with compressed air.
4. Inspect the pipe and covers for damaged sealing surfaces or restrictions within the pipe.

Water Pump Cleaning and Inspection

1. Remove the old gasket from the water pump sealing surfaces. Refer to «Replacing Engine Gaskets»(ref-200397-S39543702712005102000000) .
2. Clean all excess dirt and debris from the water pump housing.
3. Inspect the water pump (300) for the following conditions: Gasket and hose sealing surfaces for excessive scratches or gouging Restrictions within the internal coolant passages Excessive side-to-side play in the pulley shaft Leakage at the water outlet housing or rear cover gasket Leakage at the water pump vent hole A stain around the vent hole is acceptable. If leakage, such as dripping, occurs with the engine running and the cooling system pressurized, replace the water pump. Wear or damage in the belt tracking area of the pulley