Subaru Crosstrek Service Manual: Engine noise Inspection
MECHANICAL(H4DO) > Engine Noise
INSPECTION
Type of sound | Condition | Possible cause |
Regular clicking sound | Sound increases as engine speed increases. |
• Valve mechanism is defective
• Incorrect cam clearance
• Worn camshaft
• Broken valve spring
• Defective valve shim
Heavy and dull clank
Oil pressure is low.
• Worn crankshaft bearing
• Worn connecting rod bearing
Oil pressure is normal.
• Loosened flywheel mounting bolt
• Damaged engine mounting
High-pitched clank
Sound is noticeable when accelerating with an overload condition.
• Ignition timing advanced
• Accumulation of carbon inside combustion chamber
• Wrong heat range of spark plug
• Improper octane value gasoline
Clank noise when engine speed is between 1,000 and 2,000 r/min
Sound is reduced when the fuel injector connector of the noisy cylinder is disconnected.*
• Worn crankshaft bearing
• Worn connecting rod bearing
Knocking sound when engine is operating under idling speed and engine is warm
Sound is reduced when the fuel injector connector of the noisy cylinder is disconnected.*
• Worn cylinder liner and piston ring
• Broken or stuck piston ring
• Worn piston pin and piton pin hole of piston
Sound is not reduced if each fuel injector connector is disconnected in turn.*
• Unusually worn valve rocker
• Unusually worn valve shim
• Worn cam sprocket
• Worn journal of cam carrier and camshaft cap
Squeaky sound
—
• Insufficient generator lubrication
Rubbing sound
—
• Poor contact of generator brush and rotor
Gear scream when starting engine
—
• Defective ignition starter switch
• Worn gear and starter pinion
Sound like polishing glass with a dry cloth
—
• Defective V-belt tensioner assembly (loose V-belt)
• Defective water pump shaft
Hissing sound
—
• Insufficient compression
• Air leakage in air intake system, hose, connection or manifold
Timing chain noise
—
• Loose timing chain
• Timing chain contacting with adjacent part
Valve noise
—
• Incorrect cam clearance
* When disconnecting the fuel injector connector, the malfunction indicator light illuminates and DTC is stored in ECM memory.
Therefore, perform the Clear Memory Mode Clear Memory Mode > OPERATION">
and Inspection Mode Inspection Mode > PROCEDURE"> after connecting the fuel injector connector.
Crankshaft Specification
MECHANICAL(H4DO) > CrankshaftSPECIFICATIONRefer to “Cylinder Block” for removal and installation procedures of the crankshaft. Cylinder Block > REMOVAL"> Cylinder Block > ...
Engine oil pressure Inspection
MECHANICAL(H4DO) > Engine Oil PressureINSPECTION1. Disconnect the ground cable from battery. NOTE">2. Remove the oil pressure switch. Oil Pressure Switch > REMOVAL">3. Install ...
Other materials:
Preparation tool
BODY CONTROL SYSTEM (DIAGNOSTICS) > General DescriptionPREPARATION TOOL1. SPECIAL TOOLILLUSTRATIONTOOL NUMBERDESCRIPTIONREMARKS — SUBARU SELECT MONITOR 4Used for setting of each function and troubleshooting for electrical system.NOTE:For detailed operation procedures of Subaru Select Monitor 4, ...
Brake line Inspection
PERIODIC MAINTENANCE SERVICES > Brake LineINSPECTION1. BRAKE LINE1. Check for scratches, swelling, corrosion, traces of fluid leakage on the brake hoses or pipe joints.2. Make sure that brake pipes/hoses do not interfere with adjacent parts and there is no loose connector/clamp during driving.3. ...
Caution
ENGINE (DIAGNOSTICS)(H4DO) > General DescriptionCAUTION1. Airbag system wiring harness is routed near the ECM, main relay and fuel pump relay.CAUTION:• Do not use electrical test equipment on the airbag system circuits.• Be careful not to damage the airbag system wiring harness when s ...
