NO.15 ENGINE NOISE [MZ-CD 1.6]

id0103e8854800

15

Engine noise

DESCRIPTION

•  Engine noise from under hood.

POSSIBLE CAUSE

Intake-air system:

•  Detached air cleaner pipe(s).

•  Detached turbocharger pipe(s)

•  Detached charge air cooler hose(s)

Accessory drive system:

•  Accessory drive system

•  Drive belt incorrectly installed.

•  Pulley(s).

•  Lubricant or other contamination.

Noisy running:

•  Engine auxiliary components are loose or damaged.

Noisy running or valve train noise:

•  Valve clearance too large due to faulty valve tappets or worn valve train components.

•  Timing belt damaged

•  Drive belt incorrectly tensioned.

―  Drive belt chirp (Chirp is defined as a twittering noise, often intermittent)

•  Pulley misalignment (usually evident at idle).

―  Drive belt rattle (Rattle is defined as a metallic knocking noise)

•  Drive belt tensioner hitting the end stops.

•  Loose components or hardware.

―  Drive belt squeal (Squeal is defined as a continuous shriek, most noticeable when the engine is being accelerated or with electrical load.)

•  Drive belt tensioner worn, damaged or contaminated with oil.

―  Drive belt whine (Whine is defined as a continuous noise at the same frequency, generally associated with plastic pulleys.)

•  Poor surface finish on drive belt idler pulley flat surface(s).

•  Drive belt idler pulley bearing failure.

Noisy running or engine noise:

•  Engine components

―  Pistons

―  Piston rings

―  Connecting rod big end, main bearing or thrust bearing journals

―  Connecting rods bent or damaged

15	Engine noise
DESCRIPTION	• Engine noise from under hood.
POSSIBLE CAUSE	Intake-air system: • Detached air cleaner pipe(s). • Detached turbocharger pipe(s) • Detached charge air cooler hose(s) Accessory drive system: • Accessory drive system • Drive belt incorrectly installed. • Pulley(s). • Lubricant or other contamination. Noisy running: • Engine auxiliary components are loose or damaged. Noisy running or valve train noise: • Valve clearance too large due to faulty valve tappets or worn valve train components. • Timing belt damaged • Drive belt incorrectly tensioned. ― Drive belt chirp (Chirp is defined as a twittering noise, often intermittent) • Pulley misalignment (usually evident at idle). ― Drive belt rattle (Rattle is defined as a metallic knocking noise) • Drive belt tensioner hitting the end stops. • Loose components or hardware. ― Drive belt squeal (Squeal is defined as a continuous shriek, most noticeable when the engine is being accelerated or with electrical load.) • Drive belt tensioner worn, damaged or contaminated with oil. ― Drive belt whine (Whine is defined as a continuous noise at the same frequency, generally associated with plastic pulleys.) • Poor surface finish on drive belt idler pulley flat surface(s). • Drive belt idler pulley bearing failure. Noisy running or engine noise: • Engine components ― Pistons ― Piston rings ― Connecting rod big end, main bearing or thrust bearing journals ― Connecting rods bent or damaged

Diagnostic procedure

STEP	INSPECTION	RESULTS	ACTION
1	VISUALLY INSPECT RELATED PART CONDITION • Visually inspect the following: Mechanical: ― Air cleaner element ― Air cleaner intake pipe ― Air cleaner outlet pipe ― Vacuum line(s)/vacuum connections ― Charge air cooler ― Charge air cooler intake hose ― Charge air cooler outlet hose ― Damaged or contaminated drive belt ― Damaged or contaminated pulley(s) ― Incorrect drive belt ― Incorrect fitment of the drive belt ― Drive belt tensioner ― Drive belt idler pulley ― Splash shield ― Generator ― A/C compressor ― Loose hardware ― Coolant leaks ― Oil leaks ― Solenoid valve(s) ― Visibly damaged or worn parts ― Loose or missing nuts or bolts • Is there any malfunction?	Yes	Repair or replace the malfunctioning part according to the inspection results. Repeat Step 1.
1		No	Go to the next step.
2	INSPECT INTAKE-AIR SYSTEM COMPONENTS • Inspect following intake-air system component for loose installation, cracks, damaged. ― Air hose ― Ventilation hose ― Charge air inlet/outlet hose ― Intake manifold ― Charge air cooler • Is there any malfunction?	Yes	Replace the malfunctioning component and/or install the loose component properly. (See INTAKE-AIR SYSTEM REMOVAL/INSTALLATION [MZ-CD 1.6].)
2		No	Go to the next step.
3	INSPECT VACUUM HOSES • Inspect vacuum hose for loose installation, cracks, damaged. • Is there any malfunction?	Yes	Replace the malfunctioning hose and/or install the loose hose properly.
3		No	Go to the next step.
4	INSPECT INSTALLATION OF EXHAUST SYSTEM • Inspect installation of the exhaust system part. • Is there any malfunction?	Yes	Install the exhaust system properly. (See EXHAUST SYSTEM REMOVAL/INSTALLATION [MZ-CD 1.6].)
4		No	Go to the next step.
5	INSPECT ENGINE ACCESSORY COMPONENT • Inspect following accessory component for loose installation. ― A/C compressor ― Generator • Is there any loose installation?	Yes	Install the accessory components properly. (See A/C COMPRESSOR REMOVAL/INSTALLATION.) (See GENERATOR REMOVAL/INSTALLATION [MZ-CD 1.6].)
5		No	Go to the next step.
6	INSPECT DRIVE BELT • Inspect drive belt condition for following. ― Contamination (e.g. engine oil, engine coolant) ― Crack ― Exceed limit • Is there any malfunction?	Yes	Replace the drive belt. (See DRIVE BELT REMOVAL/INSTALLATION [MZ-CD 1.6].)
6		No	Go to the next step.
7	INSPECT DRIVE BELT AUTO TENSIONER • Inspect the auto tensioner. (See DRIVE BELT AUTO TENSIONER INSPECTION [MZ-CD 1.6].) • Does the drive belt auto tensioner move smoothly?	Yes	Go to the next step.
7		No	Replace the drive belt auto tensioner. (See ENGINE DISASSEMBLY/ASSEMBLY [MZ-CD 1.6].)
8	INSPECT PULLEY ALIGNMENT • Inspect the drive belt pulley alignment. • Is the alignment normal?	Yes	Go to the next step.
8		No	Install the drive belt pulley properly.
9	INSPECT ENGINE ACCESSORY COMPONENT • Inspect following accessory component for operation noise while turning on/off the system. ― A/C compressor (A/C switch and fan switch turn on and off) ― Generator (Electrical load turn on and off) • Is there excessive operation noise appeared?	Yes	Repair or replace suspect component as necessary.
9		No	Go to the next step.
10	VISUALLY INSPECT TURBOCHARGER COMPRESSOR WHEEL • Remove parts necessary to inspect the turbocharger without remove the turbocharger. • Inspect if the turbocharger compressor wheel is bent, damaged, or interfering with the housing on the vehicle. • Is there any malfunction?	Yes	Replace the turbocharger. (See EXHAUST SYSTEM REMOVAL/INSTALLATION [MZ-CD 1.6].)
10		No	Go to the next step.
11	VISUALLY INSPECT TURBOCHARGER COMPRESSOR WHEEL LOCK BOLT • Inspect if the turbocharger compressor wheel locknut is loose or has fallen down inside the turbocharger. • Is there any malfunction?	Yes	Replace the turbocharger. (See EXHAUST SYSTEM REMOVAL/INSTALLATION [MZ-CD 1.6].)
11		No	Go to the next step.
12	VERIFY TURBOCHARGER COMPRESSOR WHEEL ROTATION • Inspect the turbocharger compressor wheel by hand. • Does the wheel turn easily and smoothly?	Yes	Go to the next step.
12		No	Replace the turbocharger. • (See EXHAUST SYSTEM REMOVAL/INSTALLATION [MZ-CD 1.6].)
13	VISUALLY INSPECT TURBOCHARGER TURBINE WHEEL • Inspect if the turbocharger turbine wheel is damaged, cracked or interfering with the housing on the vehicle. Note • Inspect all fins on each turbine wheel. • Is there any malfunction?	Yes	Replace the turbocharger. (See EXHAUST SYSTEM REMOVAL/INSTALLATION [MZ-CD 1.6].)
13		No	Go to the next step.
14	INSPECT WATER PUMP • Cool down the engine. • Remove the water pump. • Visually inspect water pump. (See WATER PUMP REMOVAL/INSTALLATION [MZ-CD 1.6].) • Is there any malfunction detected?	Yes	Replace the water pump.
14		No	Go to the next step.
15	INSPECT TIMING BELT • Inspect the timing belt and pulleys for followings. ― Timing belt (contamination, cracked) ― Timing belt tensioner (move smoothly) ― Crankshaft and camshaft pulley (alignment and damaged) • Is there any malfunction?	Yes	Replace malfunctioning part. (See TIMING BELT REMOVAL/INSTALLATION [MZ-CD 1.6].)
15		No	Go to the next step.
16	INSPECT OIL PUMP • Remove the oil pump. • Visually inspect oil pump. (See OIL PUMP REMOVAL/INSTALLATION [MZ-CD 1.6].) • Is there any malfunction detected?	Yes	Replace the oil pump.
16		No	Overhaul the engine and inspect following engine internal components. • HLA • Valve clearance • Valve tappets • Valve train components • Pistons • Piston rings • Connecting rod big end, main bearing or thrust bearing journals • Connecting rods Replace malfunctioning part according to inspection result.
17	Verify test results. • If normal, return to the diagnostic index to service any additional symptoms. (See SYMPTOM DIAGNOSTIC INDEX [MZ-CD 1.6].) • If the malfunction remains, inspect the related Service Information and perform the repair or diagnosis. ― If the vehicle is repaired, troubleshooting is completed. ― If the vehicle is not repaired or additional diagnostic information is not available, reprogram the PCM if a later calibration is available. Retest.