Engine Mechanical (SOHC): Diagnosis Subaru Forester SG

INSPECTION

Scheme 69

1. After warming-up the engine, turn the ignition switch to OFF.
2. Make sure that the battery is fully charged.
3. Lower the fuel pressure. Refer to «OPERATION»(ref-200785-S18118591322005102300000) , Fuel.
4. Remove all the spark plugs.
5. Fully open the throttle valve.
6. Check the starter motor for satisfactory performance and operation.
7. Hold the compression gauge tight against spark plug hole. NOTE: When using a screw-in type compression gauge, the screw (put into cylinder head spark plug hole) should be less than 18 mm (0.71 in) long.
8. Crank the engine by means of starter motor, and then read the maximum value on the gauge when the pointer is steady.
9. Perform at least two measurements per cylinder, and make sure that the values are correct. Compression (350 rpm and fully open throttle): Standard; 1,275 kPa (13.0 kgf/cm 2 , 185 psi) Limit; 1,020 kPa (10.4 kgf/cm 2 , 148 psi) Difference between cylinders; 49 kPa (0.5 kgf/cm 2 , 7 psi), or less

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1. Before checking idle speed, check the following: Ensure the air cleaner element is free from clogging, ignition timing is correct, spark plugs are in good condition, and the hoses are connected properly. Ensure the malfunction indicator light (CHECK ENGINE light) does not illuminate.
2. Warm-up the engine.
3. Stop the engine, and then turn the ignition switch to OFF.
4. When using the SUBARU SELECT MONITOR, refer to the following. Refer to «SPECIAL TOOLS»(ref-200788-S06686206302005102300000) , General Description. Insert the cartridge to SUBARU SELECT MONITOR. Connect the SUBARU SELECT MONITOR to data link connector. Turn the ignition switch to ON, and SUBARU SELECT MONITOR switch to ON. Select the {2. Each System Check} in Main Menu. Select the {Engine Control System} in Selection Menu. Select the {1. Current Data Display & Save} in Engine Control System Diagnosis. Select the {1.12 Data Display} in Data Display Menu. Start the engine, and then read the engine idle speed.
5. When using the tachometer (Secondary pick-up type). Attach the pick-up clip to No. 1 cylinder spark plug cord. Start the engine, and then read the engine idle speed. NOTE: When using the OBD-II general scan tool, carefully read its operation manual. This ignition system provides simultaneous ignition for #1 and #2 plugs. It must be noted that some tachometers may register twice that of actual engine speed.
6. Check the idle speed when unloaded. (With headlights, heater fan, rear defroster, radiator fan, air conditioning, etc. OFF) Idle speed (No load and gears in neutral (MT vehicles), or N or P (AT vehicles) position): 650+/-100 rpm (MT vehicles) 700+/-100 rpm (AT vehicles)
7. Check the idle speed when loaded. (Turn the air conditioning switch to "ON" and operate the compressor for at least 1 minute before measurement.) Idle speed [A/C "ON", no load and gears in neutral (MT vehicles) or N or P (AT vehicles) position): 850+/-100 rpm NOTE: Idle speed can not be adjusted manually, because the idle speed is automatically adjusted. If the specified idle speed can not be maintained, refer to «IGNITION CONTROL SYSTEM»(ref-157416-S36456415262003081200000) , Basic Diagnostic Procedures.

Scheme 72

1. Warm-up the engine.
2. To check the ignition timing, connect a timing light to #1 cylinder spark plug cord, and illuminate the timing mark with timing light.
3. Start the engine at idle speed and check the ignition timing. Ignition timing [BTDC/rpm]: 10+/-8°/650 (MT vehicles) 15+/-8°/700 (AT vehicles) If the timing is not correct, check the ignition control system. Refer to Engine Control System. Refer to «IGNITION CONTROL SYSTEM»(ref-157416-S36456415262003081200000) , Basic Diagnostic Procedures.

Scheme 73

1. Warm-up the engine.
2. Disconnect the brake vacuum hose, and then install the vacuum gauge to hose fitting on manifold.
3. Keep the engine at idle speed, and then read the vacuum gauge indication. By observing the gauge needle movement, the internal condition of engine can be diagnosed as described below. Vacuum pressure (at idling, A/C "OFF"): Less than -60.0 kPa (-450 mmHg, -17.72 in-Hg) MANIFOLD VACUUM MEASURING Diagnosis of engine condition by measurement of manifold vacuum Vacuum gauge indication Possible engine condition 1. Needle is steady but lower than normal position. This tendency becomes more evident as engine temperature rises. Leakage around intake manifold gasket or disconnection or damaged vacuum hose 2. When engine speed is reduced slowly from higher speed, needle stops temporarily when it is lowering or becomes steady above normal position. Back pressure too high, or exhaust system clogged 3. Needle intermittently drops to position lower than normal position. Leakage around cylinder 4. Needle drops suddenly and intermittently from normal position. Sticky valves 5. When engine speed is gradually increased, needle begins to vibrate rapidly at certain speed, and then vibration increases as engine speed increases. Weak or broken valve springs 6. Needle vibrates above and below normal position in narrow range. Defective ignition system

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1. Disconnect the ground cable from battery.
2. Remove the generator from bracket. Refer to «REMOVAL»(ref-167630-S04585015172004101900000) , Generator.
3. Disconnect the connector from oil pressure switch.
4. Remove the oil pressure switch from engine cylinder block. Refer to «REMOVAL»(ref-200791-S30070639962005102300000) , Oil Pressure Switch.
5. Connect the oil pressure gauge hose to cylinder block.
6. Connect the battery ground cable to battery.
7. Start the engine, and then measure the oil pressure. Oil pressure: 88 kPa (0.9 kg/cm 2 ,13 psi) or more at 800 rpm 294 kPa (3.0 kg/cm 2 , 43 psi) or more at 5,000 rpm CAUTION: If the oil pressure is out of specification, check the oil pump, oil filter and lubrication line. Refer to «INSPECTION»(ref-200791-S41887185812005102300000) , Engine Lubrication System Trouble in General. If the oil pressure warning light is turned ON and oil pressure is in specification, replace the oil pressure switch. Refer to «INSPECTION»(ref-200791-S41887185812005102300000) , Engine Lubrication System Trouble in General. NOTE: The specified data is based on an engine oil temperature of 80°C (176°F).
8. After measuring the oil pressure, install the oil pressure switch. Refer to «INSTALLATION»(ref-200791-S18627085572005102300000) , Oil Pressure Switch. Tightening torque: 25 N.m (2.5 kgf-m, 18.1 ft-lb)
9. Install the generator and V-belt in the reverse order of removal, and then adjust the V-belt deflection. Refer to «INSTALLATION»(ref-200788-S14994437452005102300000) , V-belt.

Note. If out of specification, check or replace the pressure regulator and pressure regulator vacuum hose.

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1. Lower the fuel pressure. Refer to «OPERATION»(ref-200785-S18118591322005102300000) , Fuel.
2. Open the fuel flap lid, and then remove the fuel filler cap.
3. Disconnect the fuel delivery hoses from fuel filter, and then connect the fuel pressure gauge.
4. Connect the connector of fuel pump relay.
5. Start the engine.
6. Measure the fuel pressure while disconnecting the pressure regulator vacuum hose from intake manifold. Fuel pressure: Standard; 284 - 314 kPa (2.9 - 3.2 kg/cm 2 , 41- 46 psi)
7. After connecting the pressure regulator vacuum hose, measure the fuel pressure. Fuel pressure: Standard; 206 - 235 kPa (2.1 - 2.4 kg/cm 2 , 30 - 34 psi) NOTE: The fuel pressure gauge registers 10 to 20 kPa (0.1 to 0.2 kg/cm 2 , 1 to 3 psi) higher than standard values during high-altitude operations.

Note. Inspection and adjustment of the valve clearance should be performed while engine is cold.

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1. Set the vehicle on a lift.
2. Lift-up the vehicle.
3. Remove the under cover.
4. Lower the vehicle.
5. Disconnect the ground cable from battery.
6. Remove the belt cover (LH).
7. When inspecting the #1 and #3 cylinders; Disconnect the spark plug cords from spark plugs RH side. Disconnect the PCV hose from rocker cover (RH). Remove the bolts, and then remove the rocker cover (RH).
8. When inspecting the #2 and #4 cylinders; Disconnect the spark plug cords from spark plugs (LH Side). Disconnect the PCV hose from rocker cover (LH). Remove the bolts, and then remove the rocker cover (LH).
9. Set the #1 cylinder piston to top dead center of compression stroke by rotating crankshaft pulley clockwise using ST. ST 499977100 CRANK PULLEY WRENCH NOTE: When arrow mark (A) on the camshaft sprocket (LH) comes exactly to the top, #1 cylinder piston is brought to the top dead center of compression stroke.
10. Measure the #1 cylinder valve clearance by using thickness gauge. CAUTION: Insert the thickness gauge (A) in as horizontal a direction as possible with respect to the valve stem end face. Measure the exhaust valve clearances while lifting-up the vehicle. Valve clearance: Intake; 0.20+/-0.02 mm (0.0079+/-0.0008 in) Exhaust; 0.25+/-0.02 mm (0.0098+/-0.0008 in)
11. If necessary, adjust the valve clearance. Refer to «ADJUSTMENT»(ref-200788-S04776595562005102300000) , Valve Clearance.
12. Similar to measurement procedures used for #1 cylinder, measure the #2, #3 and #4 cylinder valve clearances. NOTE: Be sure to set the cylinder pistons to their respective top dead centers on compression stroke before measuring valve clearances. To set the #3, #2 and #4 cylinder pistons to their top dead centers on compression stroke, turn the crankshaft pulley clockwise 90° at a time starting with arrow mark on camshaft sprocket (LH) facing up.
13. After inspection, install the related parts in the reverse order of removal. Resonator chamber: Air cleaner case; 33 N.m (3.4 kgf-m, 25 ft-lb)

1. Make sure the pipes and hoses are installed correctly.
2. Make sure the engine coolant and ATF are at specified levels.

Make sure there are no cracks or other damage.

Scheme 87

1. After removing the engine from body, secure it in the ST shown below. ST1 498457000 ENGINE STAND ADAPTER RH ST2 498457100 ENGINE STAND ADAPTER LH ST3 499817100 ENGINE STAND
2. In this section the procedures described under each index are all connected and stated in order. It will be the complete procedure for overhauling of the engine itself when you go through all steps in the process. Therefore, in this section, to conduct the particular procedure within the flow of a section, you need to go back and conduct the procedure described previously in order to do that particular procedure.

1. Make sure the V-belt is not worn or otherwise damaged.
2. Check the tension of the belt. Refer to «INSPECTION»(ref-200788-S25611876072005102300000) , V-belt.

Scheme 88

1. Remove the V-belt. Refer to «REMOVAL»(ref-200788-S33926247212005102300000) , V-belt.
2. Remove the crankshaft pulley. Refer to «REMOVAL»(ref-200788-S02022350792005102300000) , Crankshaft Pulley.
3. Remove the belt cover (LH).
4. Remove the front belt cover.

Scheme 89

1. Install the front belt cover. Tightening torque: 5 N.m (0.5 kgf-m, 3.6 ft-lb)
2. Install the belt cover (LH). Tightening torque: 5 N.m (0.5 kgf-m, 3.6 ft-lb)
3. Install the crankshaft pulley. Refer to «INSTALLATION»(ref-200788-S33531086162005102300000) , Crankshaft Pulley.
4. Install the V-belt. Refer to «INSTALLATION»(ref-200788-S14994437452005102300000) , V-belt.

Make sure the cover is not damaged.

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1. Remove the V-belt. Refer to «REMOVAL»(ref-200788-S33926247212005102300000) , V-belt.
2. Remove the crankshaft pulley. Refer to «REMOVAL»(ref-200788-S02022350792005102300000) , Crankshaft Pulley.
3. Remove the belt cover. Refer to «REMOVAL»(ref-200788-S33590109302005102300000) , Belt Cover.
4. Remove the timing belt guide. (MT vehicles)
5. If the alignment mark (a) and/or arrow mark (which indicates rotation direction) on timing belt fade away, put new marks before removing the timing belt as shown in procedures below. Turn the crankshaft using ST. Align the mark (a) of sprocket to cylinder block notch (b) and ensure the right side cam sprocket mark (c), cam cap and cylinder head matching surface (d) and/or left side cam sprocket mark (e) and belt cover notch (f) are properly adjusted. ST 499987500 CRANKSHAFT SOCKET Using white paint, put alignment and/or arrow marks on the timing belts in relation to crank sprocket and cam sprockets. Specified data: Z 1 : 46.8 tooth length Z 2 : 43.7 tooth length
6. Remove the belt idler (No. 2).
7. Remove the belt idler No. 2.
8. Remove the timing belt.

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1. Remove the belt idler (No. 1).
2. Remove the automatic belt tension adjuster assembly.

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1. Preparation for installation of automatic belt tension adjuster assembly; CAUTION: Always use a vertical type pressing tool to move the adjuster rod down. Do not use a lateral type vise. Push the adjuster rod vertically. Press-in the push adjuster rod gradually taking more than 3 minutes. Do not allow press pressure to exceed 9,807 N (1,000 kgf, 2,205 lb). Press the adjuster rod as far as the end surface of cylinder. Do not press the adjuster rod into the cylinder. Doing so may damage the cylinder. Do not release the press pressure until stopper pin is completely inserted. Attach the automatic belt tension adjuster assembly to the vertical pressing tool. Slowly move the adjuster rod down with a pressure of 294 N (30 kgf, 66 lb) until the adjuster rod is aligned with the stopper pin hole in the cylinder. With a 2 mm (0.08 in) dia. stopper pin or a 2 mm (0.08 in) (nominal) dia. hex bar wrench inserted into the stopper pin hole in the cylinder, secure the adjuster rod.
2. Install the automatic belt tension adjuster assembly. Tightening torque: 39 N.m (4.0 kgf-m, 28.8 ft-lb)
3. Install the belt idler (No. 1). Tightening torque: 39 N.m (4.0 kgf-m, 28.9 ft-lb)

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1. Preparation for the installation of automatic belt tension adjuster assembly. Refer to «INSTALLATION»(ref-200788-S22789107912005102300000) , Timing Belt Assembly.
2. Installation of timing belt Turn the camshaft sprocket No. 2 using ST1, and then turn the camshaft sprocket No. 1 using ST2 so that their alignment marks (A) come to top positions. ST1 18231AA010 CAMSHAFT SPROCKET WRENCH NOTE: Also the CAMSHAFT SPROCKET WRENCH (499207100) can be used. ST2 499207400 CAMSHAFT SPROCKET WRENCH While aligning alignment mark on the timing belt (B) with marks on sprockets (A), position the timing belt properly.
3. Install the belt idler No. 2. Tightening torque: 39 N.m (4.0 kgf-m, 28.9 ft-lb)
4. Install the belt idler (No. 2). Tightening torque: 39 N.m (4.0 kgf-m, 28.9 ft-lb)
5. After ensuring that the marks on timing belt and camshaft sprockets are aligned, remove the stopper pin from belt tension adjuster.
6. Install the timing belt guide. (MT vehicles) Temporarily tighten the remaining bolts. Check and adjust the clearance between timing belt and timing belt guide by using thickness gauge. Clearance: 1.0+/-0.5 mm (0.039+/-0.020 in) Tighten the remaining bolts. Tightening torque: 10 N.m (1.0 kgf-m, 7.2 ft-lb)
7. Install the belt cover. Refer to «INSTALLATION»(ref-200788-S41837229032005102300000) , Belt Cover.
8. Install the crankshaft pulley. Refer to «REMOVAL»(ref-200788-S02022350792005102300000) , Crankshaft Pulley.
9. Install the V-belt. Refer to «INSTALLATION»(ref-200788-S14994437452005102300000) , V-belt.

Scheme 110

1. Check the timing belt teeth for breaks, cracks, and wear. If any fault is found, replace the belt.
2. Check the condition of back side of belt; if any crack is found, replace the belt. CAUTION: Be careful not to let oil, grease or coolant contact the belt. Remove quickly and thoroughly if this happens. Do not bend the belt sharply. Bending radius: h 60 mm (2.36 in) or more

Scheme 111

1. Visually check oil seals for leaks, and rod ends for abnormal wear or scratches. If necessary, replace faulty parts.
2. Check that the adjuster rod does not move when a pressure of 294 N (30 kgf, 66 lb) is applied to it. This is to check adjuster rod stiffness.
3. If the adjuster rod is not stiff and moves freely when applying 294 N (30 kgf, 66 lb), check it using the following procedures: Slowly press the adjuster rod down to the end surface of the cylinder. Repeat this motion 2 or 3 times. With the adjuster rod moved all the way up, apply a pressure of 294 N (30 kgf, 66 lb) to it. Check adjuster rod stiffness. If the adjuster rod is not stiff and moves down, replace the automatic belt tension adjuster assembly with a new one. CAUTION: Always use a vertical type pressing tool to move the adjuster rod down. Do not use a lateral type vise. Push the adjuster rod vertically. Press-in the push adjuster rod gradually taking more than 3 minutes. Do not allow press pressure to exceed 9,807 N (1,000 kgf, 2,205 lb). Press the adjuster rod as far as the end surface of the cylinder. Do not press the adjuster rod into the cylinder. Doing so may damage the cylinder.
4. Measure the extension of rod beyond the body. If it is not within specifications, replace with a new one. Rod extension: H 5.7+/-0.5 mm (0.224+/-0.020 in)

1. Check the sprocket teeth for abnormal wear and scratches.
2. Make sure there is no free play between sprocket and key.
3. Check the camshaft sprocket notch for sensor for damage and contamination of foreign matter.

Scheme 112

1. Remove the V-belt. Refer to «REMOVAL»(ref-200788-S33926247212005102300000) , V-belt.
2. Remove the crankshaft pulley. Refer to «REMOVAL»(ref-200788-S02022350792005102300000) , Crankshaft Pulley.
3. Remove the belt cover. Refer to «REMOVAL»(ref-200788-S33590109302005102300000) , Belt Cover.
4. Remove the timing belt assembly. Refer to «REMOVAL»(ref-200788-S26728354622005102300000) , Timing Belt Assembly.
5. Remove the camshaft sprocket. Refer to «REMOVAL»(ref-200788-S15205751072005102300000) , Camshaft Sprocket.
6. Remove the crankshaft sprocket.

Scheme 113

1. Install the crankshaft sprocket.
2. Install the camshaft sprocket. Refer to «INSTALLATION»(ref-200788-S00049029912005102300000) , Camshaft Sprocket.
3. Install the timing belt assembly. Refer to «INSTALLATION»(ref-200788-S22789107912005102300000) , Timing Belt Assembly.
4. Install the belt cover. Refer to «INSTALLATION»(ref-200788-S41837229032005102300000) , Belt Cover.
5. Install the crankshaft pulley. Refer to «INSTALLATION»(ref-200788-S33531086162005102300000) , Crankshaft Pulley.
6. Install the V-belt. Refer to «INSTALLATION»(ref-200788-S14994437452005102300000) , V-belt.

1. Check the sprocket teeth for abnormal wear and scratches.
2. Make sure there is no free play between sprocket and key.
3. Check the crankshaft sprocket notch for sensor for damage and contamination of foreign matter.

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1. Remove the V-belt. Refer to «REMOVAL»(ref-200788-S33926247212005102300000) , V-belt.
2. Remove the crankshaft pulley. Refer to «REMOVAL»(ref-200788-S02022350792005102300000) , Crankshaft Pulley.
3. Remove the belt cover. Refer to «REMOVAL»(ref-200788-S33590109302005102300000) , Belt Cover.
4. Remove the timing belt assembly. Refer to «REMOVAL»(ref-200788-S26728354622005102300000) , Timing Belt Assembly.
5. Remove the camshaft sprocket. Refer to «REMOVAL»(ref-200788-S15205751072005102300000) , Camshaft Sprocket.
6. Disconnect the PCV hose and remove rocker cover.
7. Removal of valve rocker assembly Remove the bolts (a) through (h) in alphabetical sequence. NOTE: Leave two or three threads of bolts (g and h) engaged to retain the valve rocker assembly. Remove the valve rocker assembly.

Scheme 116

1. Installation of valve rocker assembly Temporarily tighten the bolts (a) through (d) equally as shown in the figure. NOTE: Do not allow the valve rocker assembly to gouge knock pins. Tighten the bolts (e) through (h) to specified torque. Tighten the bolts (a) through (d) to specified torque. Tightening torque: 25 N.m (2.5 kgf-m, 18.1 ft-lb)
2. Adjust the valve clearances. Refer to «ADJUSTMENT»(ref-200788-S04776595562005102300000) , Valve Clearance.
3. Install the rocker cover and connect PCV hose.
4. Install the camshaft sprocket. Refer to «INSTALLATION»(ref-200788-S00049029912005102300000) , Camshaft Sprocket.
5. Install the timing belt assembly. Refer to «INSTALLATION»(ref-200788-S22789107912005102300000) , Timing Belt Assembly.
6. Install the belt cover. Refer to «INSTALLATION»(ref-200788-S41837229032005102300000) , Belt Cover.
7. Install the crankshaft pulley. Refer to «INSTALLATION»(ref-200788-S33531086162005102300000) , Crankshaft Pulley.
8. Install the V-belt. Refer to «INSTALLATION»(ref-200788-S14994437452005102300000) , V-belt.

Note. "RANK" shown in the chart refer to the possibility of reason for the trouble in order ("Very often" to "Rarely")

A - Very often

B - Sometimes

C - Rarely

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Note. When disconnecting fuel injector connector, Malfunction Indicator Light (CHECK ENGINE light) illuminates and trouble code is stored in ECM memory.

Therefore, carry out the CLEAR MEMORY MODE. Refer to CLEARING DIAGNOSTIC TROUBLE CODES .