Engine Mechanical - 5.3L: Diagnosis Chevrolet TrailBlazer I

Diagnostic Starting Point - Engine Mechanical

Begin the system diagnosis by reviewing the DISASSEMBLED VIEWS , ENGINE COMPONENT DESCRIPTION , LUBRICATION DESCRIPTION , NEW PRODUCT INFORMATION , and DRIVE BELT SYSTEM DESCRIPTION . 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 the «DIAGNOSTIC SYSTEM CHECK - ENGINE CONTROLS»(ref-158882-S07978614742003102900000) before using the symptom tables, if applicable.
2. Review the system operations in order to familiarize yourself with the system functions. Refer to «DISASSEMBLED VIEWS»(ref-188498-S11410907332005090700000) , «ENGINE COMPONENT DESCRIPTION»(ref-188498-S04213046202005090700000) , «LUBRICATION DESCRIPTION»(ref-188498-S10373810572005090700000) , «NEW PRODUCT INFORMATION»(ref-188498-S36937019152005090700000) , and «DRIVE BELT SYSTEM DESCRIPTION»(ref-188498-S33362963182005090700000) .

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 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-188498-S10855442182005090700000)
2. «BASE ENGINE MISFIRE WITH ABNORMAL INTERNAL LOWER ENGINE NOISES»(ref-188498-S12941681012005090700000)
3. «BASE ENGINE MISFIRE WITH ABNORMAL VALVE TRAIN NOISE»(ref-188498-S05062802542005090700000)
4. «BASE ENGINE MISFIRE WITH COOLANT CONSUMPTION»(ref-188498-S34862906192005090700000)
5. «BASE ENGINE MISFIRE WITH EXCESSIVE OIL CONSUMPTION»(ref-188498-S16551882702005090700000)
6. «ENGINE COMPRESSION TEST»(ref-188498-S00180194302005090700000)
7. «ENGINE NOISE ON START-UP, BUT ONLY LASTING A FEW SECONDS»(ref-188498-S27263657992005090700000)
8. «UPPER ENGINE NOISE, REGARDLESS OF ENGINE SPEED»(ref-188498-S14186992582005090700000)
9. «LOWER ENGINE NOISE, REGARDLESS OF ENGINE SPEED»(ref-188498-S33733622832005090700000)
10. «ENGINE NOISE UNDER LOAD»(ref-188498-S00183800212005090700000)
11. «ENGINE WILL NOT CRANK - CRANKSHAFT WILL NOT ROTATE»(ref-188498-S23326556212005090700000)
12. «COOLANT IN COMBUSTION CHAMBER»(ref-188498-S04128993272005090700000)
13. «COOLANT IN ENGINE OIL»(ref-188498-S12810117282005090700000)
14. «OIL CONSUMPTION DIAGNOSIS»(ref-188498-S40502742022005090700000)
15. «OIL PRESSURE DIAGNOSIS AND TESTING»(ref-188498-S16691889442005090700000)
16. «OIL LEAK DIAGNOSIS»(ref-188498-S39162353562005090700000)
17. «CYLINDER LEAKAGE TEST»(ref-188498-S34787276792005090700000)
18. «DRIVE BELT CHIRPING DIAGNOSIS»(ref-188498-S20763678902005090700000)
19. «DRIVE BELT SQUEAL DIAGNOSIS»(ref-188498-S12533391632005090700000)
20. «DRIVE BELT WHINE DIAGNOSIS»(ref-188498-S21766515482005090700000)
21. «DRIVE BELT RUMBLING DIAGNOSIS»(ref-188498-S30976568162005090700000)
22. «DRIVE BELT VIBRATION DIAGNOSIS»(ref-188498-S42094983202005090700000)
23. «DRIVE BELT FALLS OFF DIAGNOSIS»(ref-188498-S34668454402005090700000)
24. «DRIVE BELT EXCESSIVE WEAR DIAGNOSIS»(ref-188498-S37781252552005090700000)
25. «DRIVE BELT TENSIONER DIAGNOSIS»(ref-188498-S00768956032005090700000)

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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 the 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 gauge 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. Recheck the compression 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. Then 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.

Cylinder Leakage Test

Tools Required

J 35667-A Cylinder Head Leakdown Tester or equivalent

1. Disconnect the battery ground negative cable.
2. Remove the spark plugs. Refer to «SPARK PLUGS»(ref-159085-S02952502512003111400000) .
3. Rotate the crankshaft to place the piston in the cylinder being tested at top dead center (TDC) of the compression stroke.
4. Install the J 35667-A or equivalent. IMPORTANT: It may be necessary to hold the crankshaft balancer bolt to prevent the crankshaft from rotating.
5. Apply shop air pressure to the J 35667-A and adjust according to the manufacturers instructions.
6. Record the cylinder leakage value. Cylinder leakage that exceeds 25 percent is considered excessive and may require component service. In excessive leakage situations, inspect for the following conditions: Air leakage noise at the throttle body or air inlet hose that may indicate a worn or burnt intake valve or a broken valve spring. Air leakage noise at the exhaust system tailpipe that may indicate a worn or burnt exhaust valve or a broken valve spring. Air leakage noise from the crankcase, oil level indicator tube, or oil fill tube that may indicate worn piston rings, a damaged piston, a worn or scored cylinder bore, a damaged engine block or a damaged cylinder head. Air bubbles in the cooling system may indicate a damaged cylinder head or a damaged cylinder head gasket.
7. Perform the leakage test on the remaining cylinders and record the values.

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Oil Pressure Diagnosis and Testing

Tools Required

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1. J 21867 Pressure Gage
2. J 42907 Oil Pressure Testing Tool

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: Oil diluted by water or glycol anti freeze Foamy oil
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-188498-S24298136122005090700000) .
10. If the engine oil pressure is below specifications, inspect the engine for one or more of the following: Oil pump worn or dirty Refer to «OIL PUMP CLEANING AND INSPECTION»(ref-188498-S15314593702005090700000) . Oil pump-to-engine block bolts loose Refer to «OIL PUMP, PUMP SCREEN AND DEFLECTOR INSTALLATION»(ref-188498-S07585678312005090700000) . Oil pump screen loose, plugged, or damaged Oil pump screen O-ring seal missing or damaged Malfunctioning oil pump pressure regulator valve Excessive bearing clearance Cracked, porous, or restricted oil galleries Oil gallery plugs missing or incorrectly installed Refer to «ENGINE BLOCK PLUG INSTALLATION»(ref-188498-S29752830162005090700000) . Broken valve lifters Repair as necessary.
11. If the oil pressure reading on the J 21867 or equivalent is within specifications, inspect for the following: Plugged or incorrect oil filter and/or malfunctioning oil bypass valve Malfunctioning oil pressure gage or sensor Repair as necessary.

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Diagnostic Aids

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

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

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

If the squeal is intermittent, verify that it is not the accessory drive component(s) by varying their load(s), 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 belt(s) will not cause the whine. If the whine is intermittent, verify that it is not the accessory drive component(s) 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 belt(s) may have a condition that can not be seen or felt. Sometimes replacing the drive belt(s) may be the only repair for the symptom.

If after replacing the drive belt(s) and completing the diagnostic table, the rumbling is only heard with the drive belt(s) installed, there might be an accessory drive component failure. Varying the load on the accessory drive component(s) 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 belt(s) repeatedly falls off the accessory drive pulley(s), 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 belt(s) to fall off. Verify that the accessory drive component(s) are operating properly.

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

Excessive wear on a drive belt(s) is usually caused by incorrect installation or the incorrect drive belt(s) for the application.

Minor misalignment of the accessory drive pulley(s) will not cause excessive wear, but will probably cause the drive belt(s) to make a noise or fall off.

Excessive misalignment of the accessory drive pulley(s) will cause excessive wear and may also make the drive belt(s) fall off.

Engine Block Cleaning and Inspection

Tools Required

1. J 8087 Cylinder Bore Gage
2. J 42385-100 Head/Main Bolt Thread Repair Kit

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1. Clean the following areas: NOTE: Do not use a caustic solution to clean the aluminum engine block. IMPORTANT: When cleaning the engine block in a thermal type oven, do not exceed 450°F (232°C). The engine block in the solvent, to remove all sludge, dirt, or debris Refer to «CLEANLINESS AND CARE»(ref-188498-S37974590412005090700000) . CAUTION: Refer to «SAFETY GLASSES CAUTION»(ref-175132-S23208358672005041500000) in Cautions and Notices. Dry the block with compressed air. The gasket surfaces Refer to «REPLACING ENGINE GASKETS»(ref-188498-S01299503362005090700000) . The coolant passages The oil galleries The main bearing caps The engine block cylinder head bolt holes for threadlock material Thread repair driver tool J 42385-107 may be used to clean the threads of old threadlock material.
2. Inspect the following areas: The cylinder walls for excessive scratches, gouging, or ring ridge The cylinder bores for excessive ring ridge at the top of the cylinder The coolant jacket for cracks The valve lifter bores for excessive scoring or wear The crankshaft bearing webs for cracks The gasket sealing surfaces for excessive scratches or gouging Refer to «REPLACING ENGINE GASKETS»(ref-188498-S01299503362005090700000) . The oil galleries for restrictions All threaded bolt holes for damage
3. Measure the following areas: The cylinder bores for taper The cylinder bores for excessive ring ridge at the top of the cylinder

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1. Adjust the micrometer to a dimension slightly smaller than the bore size. Adjust the micrometer to 96.0 mm (3.78 in) for 5.3 liter engines.
2. Insert the bore gage into the micrometer and zero the bore gage dial.
3. Use a bore gage and measure the cylinder bore for taper, out-of-round, and oversize. Slide the bore gage up and down throughout the length of the cylinder bore. Check the bore both parallel and perpendicular to the centerline of the crankshaft at the top, center, and bottom of the bore. A 5.3L cylinder bore that measures 96.000-96.018 mm (3.779-3.78 in) may be honed and serviced with a standard size piston. A cylinder bore that exceeds the maximum diameter must be serviced with an oversized piston.

Crankshaft and Bearings Cleaning and Inspection

Tools Required

1. J 6125-1B Slide Hammer
2. J 7872 Magnetic Base Dial Indicator Set
3. J 36660-A Torque Angle Meter
4. J 41818 Crankshaft Bearing Cap Remover
5. J 43690 Rod Bearing Checking Tool
6. J 43690-100 Rod Bearing Checking Tool - Adapter Kit

Inspection Procedure

Imperfections of the reluctor ring teeth may effect OBD II system performance.

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1. Perform a visual inspection of the crankshaft for damage.
2. Inspect the crankshaft position reluctor ring lobes 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 key (1), keyway (2), and threaded hole (3) for damage.
8. Measure the crankpins for the out-of-round.
9. Measure the crankpins for taper.
10. Measure the crankshaft thrust wall width. A crankshaft with a thrust wall width in excess of 26.2 mm (1.0315 in) must be replaced.
11. Measure the crankshaft runout. Use wooden V blocks or a fixture to support the crankshaft on the front and rear journals.
12. Use the J 7872 in order to measure the crankshaft runout at the front and rear intermediate journals.
13. Use the J 7872 in order to measure the runout of the crankshaft rear flange.
14. 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.
15. Inspect crankshaft bearings for craters or pockets. Flattened sections on the bearing halves also indicate fatigue.
16. Inspect the crankshaft bearings for excessive scoring or discoloration.
17. Inspect the crankshaft bearings for dirt or debris imbedded into the bearing material.
18. 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.

Camshaft and Bearings Cleaning and Inspection

Tools Required

1. J 7872 Magnetic Base Dial Indicator Set
2. J 8520 Camshaft Lobe Lift Indicator

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1. Clean the components in solvent. CAUTION: Refer to «SAFETY GLASSES CAUTION»(ref-175132-S23208358672005041500000) in Cautions and Notices.
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, (4) for damage.
7. Inspect the camshaft position reluctor ring for nicks or damage.
8. Inspect the camshaft retainer plate for wear or a damaged sealing gasket. If the camshaft retainer plate sealing gasket is not cut or damaged, it may be used again.
9. 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.
10. Inspect the camshaft bearings for excessive wear or scoring. Bearings with excessive scoring or wear must be replaced.
11. Measure the camshaft journals for wear and out-of-round with a micrometer. If the camshaft bearing journals are more than 0.025 mm (0.001 in) out-of-round, replace the camshaft. If the camshaft bearing journal diameter is less that 54.99 mm (2.164 in), replace the camshaft.
12. Measure the camshaft lobes for wear with a micrometer. A 5.3L camshaft with an intake lobe that measures 46.169 mm (1.817 in) or less must be replaced. A 5.3L camshaft with an exhaust lobe that measures 46.199 mm (1.818 in) or less must be replaced.
13. Measure the camshaft runout. 13.1. Mount the camshaft in wooden V blocks or between centers on a fixture. 13.2. Check the runout of the intermediate camshaft bearing journals using the J 7872 . 13.3. If camshaft runout exceeds 0.05 mm (0.002 in), the camshaft is bent and should be replaced.

Valve Rocker Arm and Push Rods Cleaning and Inspection

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1. Mark, sort, or organize the components for assembly. Refer to «SEPARATING PARTS»(ref-188498-S17158006432005090700000) .
2. Clean the components with cleaning solvent. CAUTION: Refer to «SAFETY GLASSES CAUTION»(ref-175132-S23208358672005041500000) in Cautions and Notices.
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 pivot supports for cracks, wear, or other damage.

Valve Lifters and Guides Cleaning and Inspection

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1. Mark, sort, or organize the components for assembly. Refer to «SEPARATING PARTS»(ref-188498-S17158006432005090700000) .
2. Clean the components in cleaning solvent. CAUTION: Refer to «SAFETY GLASSES CAUTION»(ref-175132-S23208358672005041500000) in Cautions and Notices.
3. Dry the components with compressed air.
4. Inspect the valve lifters for the following: Bent or broken clip (1) Worn pushrod socket (2) Scuffed or worn sides (3) If the valve lifter shows wear, inspect the engine block lifter bores for wear or damage. Flat spots on the roller (4) Loose or damaged pin (5) Plugged oil hole (6) Worn or damaged roller bearing The roller should rotate freely with no binding or roughness
5. Inspect the valve lifter guides for the following: For cracks or damage Excessive wear in the lifter mounting bores

Cylinder Head Cleaning and Inspection

Tools Required

1. J 8089 Carbon Removal Brush
2. J 9666 Valve Spring Tester

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1. Clean the following components: CAUTION: Refer to «SAFETY GLASSES CAUTION»(ref-175132-S23208358672005041500000) in Cautions and Notices. IMPORTANT: Be careful not to scuff the chamber. Use the J 8089 in order to remove the carbon from the combustion chambers. Gasket surfaces Refer to «REPLACING ENGINE GASKETS»(ref-188498-S01299503362005090700000) . Valve stems and heads on a buffing wheel Bolt hole threads Remove all dirt, debris, or threadlock material from the bolt holes.
2. Inspect the following: 2.1. Worn or loose valve seats (8 or 11) 2.2. The cylinder head for cracks in the exhaust ports and combustion chambers 2.3. The cylinder head for external cracks in the water chambers 2.4. The gasket surfaces for excessive scratches or gouging Refer to «REPLACING ENGINE GASKETS»(ref-188498-S01299503362005090700000) . 2.5. The bolt hole threads for debris or damaged threads Refer to «THREAD REPAIR»(ref-188498-S10230912542005090700000) or «THREAD REPAIR SPECIFICATIONS»(ref-188498-S32236017312005090700000) .
3. Inspect the cylinder head for warpage. Refer to «ENGINE MECHANICAL SPECIFICATIONS»(ref-188498-S24298136122005090700000) .
4. Inspect the valve springs for squareness.
5. Use the J 9666 in order to measure the valve spring tension. Replace the spring if the spring tension is less than 310 N (70 lb) at 45.75 mm (1.80 in).

Oil Pump Cleaning and Inspection

The oil pump pipe and screen are to be serviced as an assembly. Do not attempt to repair the wire mesh portion of the pump and screen assembly.

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1. Clean the parts in solvent. CAUTION: Refer to «SAFETY GLASSES CAUTION»(ref-175132-S23208358672005041500000) in Cautions and Notices.
2. Dry the parts with compressed air.
3. Inspect the oil pump housing and the cover 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 and plug bore for damaged threads.
7. Inspect the oil pump internal oil passages for restrictions.
8. Inspect the drive gear and driven gear 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 and bore for scoring or wear. The valve must move freely in the bore with no restrictions.
11. Inspect the oil pump screen for debris or restrictions.
12. Inspect the oil pump screen for broken or loose wire mesh.

Engine Front Cover Cleaning and Inspection

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1. Remove the crankshaft oil seal (1) 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-188498-S01299503362005090700000) . CAUTION: Refer to «SAFETY GLASSES CAUTION»(ref-175132-S23208358672005041500000) in Cautions and Notices.
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.

Engine Rear Cover Cleaning and Inspection

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1. Remove the crankshaft oil seal (1) 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-188498-S01299503362005090700000) . CAUTION: Refer to «SAFETY GLASSES CAUTION»(ref-175132-S23208358672005041500000) in Cautions and Notices.
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.

Engine Valley Cover Cleaning and Inspection

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1. Remove the knock sensor oil seals (1) from the valley cover (2).
2. Clean the valley cover in solvent. CAUTION: Refer to «SAFETY GLASSES CAUTION»(ref-175132-S23208358672005041500000) in Cautions and Notices.
3. Dry the valley cover with compressed air.
4. Inspect the gasket sealing surfaces for excessive scratches or gouging. Refer to «REPLACING ENGINE GASKETS»(ref-188498-S01299503362005090700000) .
5. Inspect the valley cover oil seal bores for excessive scratches or gouging.

Valve Rocker Arm Cover Cleaning and Inspection

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1. Remove the ignition coil and bracket assembly, bolts, and wire harness from the left cover, if required.
2. Remove the ignition coil and bracket assembly, bolts, and wire harness from the right cover, if required.
3. Inspect the tube for a loose fit or damage.
4. Remove the oil fill cap and tube from the right cover, if required.
5. Remove the gaskets (1) from the covers.
6. Remove the cover mounting bolts, with grommets. Cover mounting bolts and grommets that are not damaged may be used again during assembly.
7. Clean the covers in solvent. CAUTION: Refer to «SAFETY GLASSES CAUTION»(ref-175132-S23208358672005041500000) in Cautions and Notices.
8. Dry the covers with compressed air.
9. Inspect the ventilation system passages for restrictions.
10. Inspect the gasket grooves for damage.
11. Inspect the coil bracket threaded bolt holes for damage or debris.

Oil Pan Cleaning and Inspection

Do not reuse the oil pan to engine block gasket. Install a NEW gasket during assembly.

When installing a NEW oil pan gasket, it is not necessary to install the rivets that retain the NEW gasket to the pan.

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1. Remove the oil transfer tube bolts (1) and gaskets (3).
2. Remove the oil transfer tube (2).
3. Inspect the tube for damage or restrictions.
4. Remove the plugs (1) from the oil galleries.
5. Remove the oil pan baffle and bolts.
6. Remove the oil pan drain plug and O-ring seal.
7. Clean the oil pan in solvent. Be sure to thoroughly clean all of the oil passages and recesses of the pan.
8. Clean the oil pan gasket surfaces. Refer to «REPLACING ENGINE GASKETS»(ref-188498-S01299503362005090700000) . CAUTION: Refer to «SAFETY GLASSES CAUTION»(ref-175132-S23208358672005041500000) in Cautions and Notices.
9. Dry the oil pan with compressed air.
10. Inspect the gasket sealing surfaces for excessive scratches or gouging. Refer to «REPLACING ENGINE GASKETS»(ref-188498-S01299503362005090700000) .
11. Inspect the oil pan drain plug and threaded drain hole for damaged threads. The drain plug O-ring seal may be used again if not cut or damaged.
12. Inspect the oil filter sealing surface for scratches or gouging.
13. Inspect the oil filter fitting (1) for a loose fit or damaged threads.
14. Inspect the oil passages for restrictions.
15. Inspect the oil filter bypass valve (2) for proper operation. Lightly depress the bypass valve. The valve spring should seat the valve to the proper position.

Exhaust Manifold Cleaning and Inspection

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1. Clean the exhaust manifold (1) and heat shield (2) 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 or damaged heat shield (2).
5. Inspect the take down studs 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

Scheme 122

Scheme 123

1. Remove the sealing gaskets from the pipe.
2. Remove the sealing gaskets from the covers.
3. Clean the pipe (2), hose (1), and covers in solvent. CAUTION: Refer to «SAFETY GLASSES CAUTION»(ref-175132-S23208358672005041500000) in Cautions and Notices.
4. Dry the pipe and covers with compressed air.
5. Inspect the pipe and covers for damage or restrictions.
6. Inspect the gasket and hose sealing surfaces for damage.
7. Inspect the hose (1) for restrictions, cracking or wear. The hose may be used again if it is not damaged.

Scheme 124

Scheme 125

1. Remove the old gasket from the water pump sealing surfaces. Refer to «REPLACING ENGINE GASKETS»(ref-188498-S01299503362005090700000) .
2. Clean all excess dirt and debris from the water pump housing.
3. Inspect the water pump for the following: 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, dripping, occurs with the engine running and the cooling system pressurized, replace the water pump.
4. Inspect the water pump pulley for wear or damage in the belt tracking area.

Engine Mechanical Diagnostic Procedure Revisions

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 problem. The diagnostic flow is the place to start when repairs are necessary. For a detailed explanation, refer to STRATEGY BASED DIAGNOSIS in General Information or DIAGNOSTIC STARTING POINT - ENGINE MECHANICAL .