Engine Mechanical (H4SO): Diagnosis Subaru Forester SH

INSPECTION

Scheme 102

1. After warming-up the engine, turn the ignition switch to OFF.
2. Make sure that the battery is fully charged.
3. Release the fuel pressure. Refer to «RELEASING OF FUEL PRESSURE»(ref-325305-S19314969582009071800000) , PROCEDURE, Fuel .
4. Remove all the spark plugs. Refer to «REMOVAL»(ref-325317-S24389803832009071800000) , Spark Plug .
5. Fully open the throttle valve.
6. Check the starter motor for satisfactory performance and operation.
7. Hold the compression gauge tightly against the spark plug hole. NOTE: When using a screw-in type compression gauge, the screw should be less than 18 mm (0.71 in) long.
8. Crank the engine by the starter motor, and read the maximum value on the gauge when the needle of gauge is steady.
9. Perform at least two measurements per cylinder, and check that the values are correct. Compression (Fully open throttle): Standard 1,020 - 1,275 kPa (10.4 - 13.0 kgf/cm 2 , 148 - 185 psi) Difference between cylinders 49 kPa (0.5 kgf/cm 2 , 7 psi), or less
10. After inspection, install the related parts in the reverse order of removal.

1. Before checking the idle speed, check the following item: Check the air cleaner element is free from clogging, ignition timing is correct, spark plugs are in good condition, and hoses are connected properly. Check the malfunction indicator light does not illuminate.
2. Warm-up the engine.
3. Read the engine idle speed using Subaru Select Monitor. Refer to «READ CURRENT DATA FOR ENGINE (NORMAL MODE)»(ref-325319-S03162793802009071800000) , OPERATION, Subaru Select Monitor .
4. Check the idle speed when no-loaded. (Headlight, heater fan, rear defroster, radiator fan, A/C and etc. are OFF) Idle speed [No load and gears in neutral, "P" or "N" range]: 650±100 RPM (MT model) 700±100 RPM (AT model)
5. Check the idle speed under load condition. (Turn the A/C switch to "ON" and operate the compressor for at least one minute before measurement). Idle speed [A/C ON and gears in neutral, "P" or "N" range]: 850±100 RPM

Note. Idle speed cannot be adjusted manually, because the idle speed is automatically adjusted. If the specified idle speed cannot be maintained, refer to the General On-board Diagnosis Table under "Engine Control System". Refer to BASIC DIAGNOSTIC PROCEDURE .

Scheme 103

1. Before checking the ignition timing, check the following item: Check the air cleaner element is free from clogging, spark plugs are in good condition, and hoses are connected properly. Check the malfunction indicator light does not illuminate.
2. Warm-up the engine.
3. Stop the engine, and turn the ignition switch to OFF.
4. Connect the timing light to #1 cylinder spark plug cord, and then light the timing mark with the timing light.
5. Start the engine and check the ignition timing at idle speed as shown in the figure below. Ignition timing [BTDC/RPM]: 10°±8°/650 (MT Model) 15°±10°/700 (AT Model) If the timing is not correct, check the ignition control system. Refer to «BASIC DIAGNOSTIC PROCEDURE»(ref-325319-S40932044202009071800000) .

Scheme 104

1. Warm-up the engine.
2. Disconnect the brake vacuum hose from intake manifold, and then install the vacuum gauge.
3. Keep the engine at idle speed and read the vacuum gauge indication. By observing the gauge needle movement, the internal condition of the engine can be diagnosed as described below. Vacuum pressure (at idling, A/C "OFF"): Less than -60.0 kPa (-450 mmHg, -17.72 inHg) VACUUM PRESSURE SPECIFICATION Diagnosis of engine condition by measurement of intake 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. Air leakage around intake manifold gasket, disconnection or damage of vacuum hose 2. Needle intermittently drops to position lower than normal position. Leakage around cylinder 3. Needle drops suddenly and intermittently from normal position. Sticky valve 4. 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 5. Needle vibrates above and below normal position in narrow range. Defective ignition system

Scheme 105

Scheme 106

1. Disconnect the ground cable from the battery.
2. Remove the oil pressure switch. Refer to «REMOVAL»(ref-325324-S21282559982009071800000) , Oil Pressure Switch .
3. Connect the oil pressure gauge to cylinder block.
4. Connect the ground cable to battery.
5. Start the engine, and measure the oil pressure. Oil pressure: Standard 98 kPa (1.0 kg/cm 2 , 14 psi) or more at 600 RPM 294 kPa (3.0 kg/cm 2 , 43 psi) or more at 5,000 RPM If the oil pressure is out of specification, check oil pump, oil filter and lubrication line. Refer to «INSPECTION»(ref-325324-S21153331132009071800000) , Engine Lubrication System Trouble in General . If the oil pressure warning light is ON and oil pressure is within specification, check the oil pressure switch. Refer to «INSPECTION»(ref-325324-S21153331132009071800000) , Engine Lubrication System Trouble in General . NOTE: Standard value is based on an engine oil temperature of 80°C (176°F).
6. After measuring the oil pressure, install the oil pressure switch. Refer to «INSTALLATION»(ref-325324-S09963747752009071800000) , Oil Pressure Switch .

Note. Check or replace the fuel pump and fuel delivery line if the fuel pressure is out of the standard.

Scheme 107

Scheme 108

1. Release the fuel pressure. Refer to «RELEASING OF FUEL PRESSURE»(ref-325305-S19314969582009071800000) , PROCEDURE, Fuel .
2. Disconnect the fuel delivery hose from the fuel damper, and connect the fuel pressure gauge.
3. Install the fuse of fuel pump to main fuse box.
4. Start the engine.
5. Measure the fuel pressure after warming up the engine. 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. Fuel pressure: Standard: 338 - 348 kPa (3.4 - 3.5 kg/cm 2 , 49 - 50 psi)

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

Scheme 109

Scheme 110

Scheme 111

Scheme 112

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 the battery.
6. Remove the timing belt cover LH.
7. Remove the fuel injector. Refer to «REMOVAL»(ref-325305-S28308164462009071800000) , Fuel Injector .
8. When inspecting #1 and #3 cylinders Disconnect the spark plug cords from spark plugs RH side. Refer to «RH SIDE»(ref-325317-S01945246792009071800000) , REMOVAL, Spark Plug . Place a suitable container under the vehicle. Disconnect the PCV hose from the rocker cover RH. NOTE: Fit the depression in the ST with the protrusion of the clamp as shown in the figure below, and unlock the clamp. ST 18353AA000 CLAMP PLIERS Remove the bolts, then remove the rocker cover RH.
9. When inspecting #2 and #4 cylinders Disconnect the spark plug cords from spark plugs LH side. Refer to «LH SIDE»(ref-325317-S19345806642009071800000) , REMOVAL, Spark Plug . Place a suitable container under the vehicle. Disconnect the PCV hose from the rocker cover LH. NOTE: Fit the depression in the ST with the protrusion of the clamp as shown in the figure below, and unlock the clamp. ST 18353AA000 CLAMP PLIERS Remove the bolts, then remove the rocker cover LH.
10. Set #1 cylinder piston to top dead center of compression stroke by rotating the crank pulley clockwise using the socket wrench. NOTE: When the arrow mark (A) on cam sprocket LH is at the top position, the #1 cylinder piston is at top dead center of the compression stroke.
11. Measure #1 cylinder valve clearance by using thickness gauge (A). NOTE: Insert the thickness gauge (A) in as horizontally as possible with respect to the valve stem end face. Lift up the vehicle and measure the exhaust valve clearances. Valve clearance: Intake 0.20±0.04 mm (0.0079±0.0016 in) Exhaust 0.25±0.04 mm (0.0098±0.0016 in)
12. If necessary, adjust the valve clearance. Refer to «ADJUSTMENT»(ref-325301-S24451996572009071800000) , Valve Clearance .
13. Measure the valve clearance in #3, #2 and #4 cylinder in the same measurement procedure as #1 cylinder in this order. NOTE: Be sure to set the cylinder pistons to their respective top dead centers on compression stroke before measuring valve clearances. By rotating the crank pulley clockwise every 180° from the state that #1 cylinder piston is on the top dead center of compression stroke, #3, #2 and #4 cylinder pistons come to the top dead center of compression stroke in this order.
14. After inspection, install the related parts in the reverse order of removal. NOTE: Use a new rocker cover gasket. For the PCV hose clamp, use a new clamp. Sandwich the protruding part of the clamp with the ST and lock the clamp. ST 18353AA000 CLAMP PLIERS

1. Check that pipes, hoses, connectors and clamps are installed firmly.
2. Check the engine coolant is at specified level.
3. Check that the ATF is at specified level. (AT model)
4. Start the engine and check for exhaust gas, engine coolant, leaks of fuel, etc. Also check for noise and vibrations.

Make sure that no crack or other damages do not exist.

Scheme 113

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

1. Make sure the V-belts are not worn or otherwise damaged.
2. Check the tension of the front side belt. Refer to «INSPECTION»(ref-325301-S29407796552009071800000) , V-belt .

Check the timing belt cover for damage.

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

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

Note. The "RANK" shown in the chart shows the possibilities of the cause of trouble in order from "Very often" to "Rarely".

A - Very often

B - Sometimes

C - Rarely

PROBLEM SYMPTOMS

ENGINE NOISE CONDITION