Engine Mechanical (H4DOTC): Diagnosis Subaru Forester SH

INSPECTION

1. Remove the collector cover.
2. After warming-up the engine, turn the ignition switch to OFF.
3. Make sure that the battery is fully charged.
4. Release the fuel pressure. Refer to «RELEASING OF FUEL PRESSURE»(ref-325306-S29431132992009071800000) , PROCEDURE, Fuel .
5. Remove all the spark plugs. Refer to «REMOVAL»(ref-325338-S12180694772009071800000) , Spark Plug .
6. Fully open the throttle valve.
7. Check the starter motor for satisfactory performance and operation.
8. 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.
9. Crank the engine by the starter motor, and read the maximum value on the gauge when the needle of gauge is steady.
10. Perform at least two measurements per cylinder, and check that the values are correct.
11. 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-325335-S37463705132009071800000) , 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 "P" or "N" range]: 700 ± 100 RPM
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 "P" or "N" range]: 825 ± 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 .

1. Warm-up the engine.
2. Remove the collector cover.
3. Remove the intercooler. Refer to «REMOVAL»(ref-325300-S41039960822009071800000) , Intercooler .
4. Disconnect the brake booster vacuum hose from the intake manifold, and then install the vacuum gauge.
5. Install the intercooler. Refer to «INSTALLATION»(ref-325300-S37233999532009071800000) , Intercooler .
6. 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.

Scheme 325

Vacuum pressure (at idling, A/C OFF)

Less than -68.0 kPa (-510 mmHg, -20.08 inHg)

ENGINE CONDITION CHART

Scheme 326

Scheme 327

1. Remove the collector cover.
2. Disconnect the ground cable from the battery.
3. Remove the oil pressure switch. Refer to «REMOVAL»(ref-325339-S08716690352009071800000) , Oil Pressure Switch .
4. Connect the oil pressure gauge hose to cylinder block.
5. Connect the battery ground cable to the battery.
6. Start the engine, and measure the oil pressure. Oil pressure: Standard 98 kPa (1.0 kgf/cm 2 , 14 psi) or more (at 600 RPM) 294 kPa (3.0 kgf/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-325339-S30160856992009071800000) , 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-325339-S30160856992009071800000) , Engine Lubrication System Trouble in General . NOTE: Standard value is based on an engine oil temperature of 80°C (176°F).
7. After measuring the oil pressure, install the oil pressure switch. Refer to «INSTALLATION»(ref-325339-S23907751702009071800000) , Oil Pressure Switch .

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

Scheme 328

Scheme 329

1. Remove the collector cover.
2. Release the fuel pressure. Refer to «RELEASING OF FUEL PRESSURE»(ref-325306-S29431132992009071800000) , PROCEDURE, Fuel .
3. Open the fuel filler lid, and remove the fuel filler cap.
4. Disconnect the fuel delivery hose from the fuel damper, and connect the fuel pressure gauge.
5. Install the fuse of fuel pump to the main fuse box.
6. Start the engine.
7. Measure the fuel pressure while disconnecting the pressure regulator vacuum hose from the intake manifold. NOTE: The fuel pressure gauge registers 10 to 20 kPa (0.1 to 0.2 kgf/cm 2 , 1 to 3 psi) higher than standard values during high-altitude operations. Fuel pressure: Standard 284 - 314 kPa (2.9 - 3.2 kgf/cm 2 , 41 - 46 psi)
8. After connecting the pressure regulator vacuum hose, measure the fuel pressure.

Note. The fuel pressure gauge registers 10 to 20 kPa (0.1 to 0.2 kgf/cm 2 , 1 to 3 psi) higher than standard values during high-altitude operations.

Fuel pressure

Standard

230 - 260 kPa (2.35 - 2.65 kgf/cm 2 , 33 - 38 psi)

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

Scheme 330

Scheme 331

Scheme 332

Scheme 333

Scheme 334

Scheme 335

1. Set the vehicle on a lift.
2. Remove the collector cover.
3. Disconnect the ground cable from the battery.
4. Remove the air intake duct (rear). Refer to «REMOVAL»(ref-325300-S04200539772009071800000) , Air Intake Duct .
5. Remove the bolt which secures timing belt cover RH.
6. Lift up the vehicle.
7. Remove the under cover.
8. Loosen the remaining bolts which secure timing belt cover RH, then remove the timing belt cover.
9. Lower the vehicle.
10. When inspecting #1 and #3 cylinders Remove the air cleaner case. Refer to «REMOVAL»(ref-325300-S05802953992009071800000) , Air Cleaner Case . Remove the ignition coil. Refer to «REMOVAL»(ref-325338-S36569430992009071800000) , Ignition Coil . Place a suitable container under the vehicle. Disconnect the PCV hose from the rocker cover RH. NOTE: For the PCV hose affixed with the clamp, fit the depression in the ST with the protrusion of the clamp as shown in the figure below, unlock the clamp and disconnect. ST 18353AA000 CLAMP PLIERS Remove the bolts, then remove the rocker cover RH.
11. When inspecting #2 and #4 cylinders Disconnect the battery cable, and remove the battery from the vehicle. Remove the secondary air pump. Refer to «REMOVAL»(ref-325337-S21607419822009071800000) , Secondary Air Pump . Remove the ignition coil. Refer to «REMOVAL»(ref-325338-S36569430992009071800000) , Ignition Coil . Place a suitable container under the vehicle. Disconnect the PCV hose from the rocker cover LH. NOTE: For the PCV hose affixed with the clamp, fit the depression in the ST with the protrusion of the clamp as shown in the figure below, unlock the clamp and disconnect. ST 18353AA000 CLAMP PLIERS Remove the bolts, then remove the rocker cover LH.
12. Turn the crank pulley clockwise until the round mark and arrow mark on the camshaft sprocket are set to position shown in the figure. NOTE: Turn the crank pulley using a socket wrench.
13. Measure the #1 cylinder intake valve and #3 cylinder exhaust valve clearance by using thickness gauge (A). NOTE: Insert a thickness gauge in a direction as horizontal as possible with respect to the valve lifter. Lift up the vehicle and measure the exhaust valve clearances. If the measured value is not within specification, take notes of the value in order to adjust the valve clearance later on. Valve clearance (inspection value): Intake 0.20 +0.04 -0.06 mm (0.0079 +0.0016 -0.0024 in) Exhaust 0.35 ± 0.05 mm (0.0138 ± 0.0020 in)
14. If necessary, adjust the valve clearance. Refer to «ADJUSTMENT»(ref-325302-S17591177352009071800000) , Valve Clearance .
15. Further turn the crank pulley clockwise and then measure the valve clearances again. Set the round mark and arrow mark on cam sprocket to the position shown in the figure, and measure the #2 cylinder exhaust valve and #3 cylinder intake valve clearances. Set the round mark and arrow mark on cam sprocket to the position shown in the figure, and measure the #2 cylinder intake valve and #4 cylinder exhaust valve clearances. Set the round mark and arrow mark on cam sprocket to the position shown in the figure, and measure the #1 cylinder exhaust valve and #4 cylinder intake valve clearances.
16. After inspection, install the related parts in the reverse order of removal.

Note. Use a new rocker cover gasket. For the PVC 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 that the engine coolant is at specified level.
3. Check that the ATF is at specified level.
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 336

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. Check the V-belt is not worn or otherwise damaged.
2. Check the tension of the front side belt. Refer to «INSPECTION»(ref-325302-S10218105432009071800000) , 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.

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

ENGINE TROUBLE SYMPTOM CHART

ENGINE NOISE CONDITION CHART