Noise when accelerating: which faults cause it?

The most important among the documented faults: MHSG belt tensioner and crankshaft pulley failure (48V mild hybrid), in the 1.6 CRDi; wear of the variator chain and cones, in the Multitronic; turbo failure through lack of lubrication (carbon deposits and union filter), in the 1.6 HDi; variable-geometry turbo failures (actuator, sensors and clogging), in the 2.0 HDi; premature turbocharger failure or wear, in the 1.4 T-Jet; turbo wear or failure from lack of lubrication, in the Skyactiv-D; premature turbocharger failure, in the 1.6 EcoBoost; turbocharger wear and loss of performance, in the 1.1 and 1.4 CRDi.

NoisesUrgency: Garage soon

Noise when accelerating: causes and the faults that trigger it

A noise when accelerating rarely has a single cause. The sources consulted point mainly to the exhaust system, the dual-mass flywheel, the engine mounts, the CV joints and the turbo or its hoses, and the type of sound (whistle, roar, rattle, metallic knock) and when it occurs are clues, not a diagnosis. A metallic noise heard when accelerating should not be ignored: have a garage check it.^{[1][2][3][4][5][6][7]}

15 documented faults cause it in 15 engines. The most important:

Critical severity: MHSG belt tensioner and crankshaft pulley failure (48V mild hybrid) · 1.6 CRDi
Critical severity: Wear of the variator chain and cones · Multitronic
High severity: Turbo failure through lack of lubrication (carbon deposits and union filter) · 1.6 HDi

What it means

A noise that appears or changes when you press the accelerator can come from the exhaust, the dual-mass flywheel, the engine mounts, the driveshafts or the turbo. The type of sound (whistle, roar, rattle, metallic knock) and when it appears point towards the cause, but do not confirm it.

General explanation from MotorFiable. How it shows up in each engine, with sources, is in the list of faults.

What to do now

Garage soon

Note when it happens (engine cold or warm, at what speed, in a straight line or turning) and do not ignore it: ask for an inspection at a garage before the noise gets worse.

Reviewed on 5 October 202628 sources How we work

Most common causes

From most to least likely according to the sources. Under each cause, the part and the related OBD codes.

1. Exhaust leak or damage
Common cause
Autodoc Club lists among the signs of a faulty exhaust an engine roar that changes pitch when accelerating and a rattling under the car, and warns that if the floor of the cabin gets hot, the heat shields have burnt away. A leak at the manifold makes the engine sound considerably louder and, with a cold engine, can produce a "tick"; a damaged flexible pipe or silencer can cause whistling.^[1][2][8]
2. Worn dual-mass flywheel
Common cause
RACE includes among the symptoms of a worn dual-mass flywheel knocks when starting or switching off the engine and abnormal vibrations or noises at idle or while driving. Autofácil explains that when it is badly deteriorated, the metallic noise can be heard when accelerating, and that the fault is then serious: there have been cases where it has broken and damaged the gearbox housing.^[3][4][9]
Faults with with the dual-mass flywheel Faults with with the clutch
3. Worn engine mounts
Possible cause
With worn engine mounts, Diariomotor describes engine vibrations being felt more inside the car and the engine visibly moving when you lift off the accelerator. Autodoc Club lists vibration accompanied by noise among the signs of worn mounts or a faulty spark plug.^[1][5]
Faults with with the crankshaft pulley and engine mounts
4. Worn CV joint
Possible cause
RACE links to CV joints a shudder felt through the floor, the seat or the gear lever, especially when accelerating hard or going over 80 km/h, and a "clack-clack" heard with the steering on full lock at low speed. Grease thrown out by the wheel gives away a split boot.^[6]
Faults with with the driveshafts and transmission
5. Faulty turbo or leaking hose
Possible cause
Autodoc Club points out that a slight whistle when accelerating can be normal in a turbocharged car, but one that is too loud can indicate a leak in a hose. RACE includes whistling from the engine area, together with loss of power, among the symptoms of a broken or faulty turbo.^[1][7]
Faults with with the turbo
6. Engine knock (detonation)
Possible cause
Autodoc Club attributes a loud metallic noise in a relatively new engine to detonation caused by low-octane fuel. Its article on the knock sensor lists knocking when accelerating, pinging, loss of power and the engine warning light among the symptoms of a failing sensor.^[1][10]
Faults with with the engine sensors
7. Stretched timing chain or internal engine wear
Uncommon
Autodoc Club associates a rattle with a stretched timing chain, a ticking with a cold engine with a valve fault, and uneven knocks from the sump area with the crankshaft bearings. Its recommendation is not to ignore these noises, to have the car checked and to repair the affected component.^[1]
Faults with with the timing chain Faults with with the big-end bearings and pistons

Depending on what you notice

Noise when accelerating at low revs

None of the sources consulted links the noise to a specific engine speed, so on its own it does not allow causes to be ruled out. Among the most frequently cited causes of noises and vibrations at idle or while driving are the dual-mass flywheel (RACE) and the engine mounts (Diariomotor, which describes an engine visibly moving when you lift off the accelerator). If the metallic noise is already audible when accelerating, Autofácil considers it a sign of a badly deteriorated dual-mass flywheel.^[3][4][5]

Metallic noise when accelerating

Autodoc Club distinguishes several metallic noises: a rattle from a stretched timing chain, uneven knocks from the crankshaft bearings and, in a relatively new engine, a loud noise that may be detonation from low-octane fuel. Autofácil adds that a metallic noise heard when accelerating is a sign of a badly deteriorated dual-mass flywheel. In every case Autodoc recommends not ignoring it.^[1][4]

Noise when accelerating while driving

If the shudder appears when accelerating hard or past around 80 km/h, RACE links it to the CV joints and warns that if one seizes at high speed, there can be a critical loss of control. A roar that changes pitch when accelerating points, according to Autodoc Club, to the exhaust; a whistle, to the turbo or a hose.^[1][2][6]

Noisy at idle and goes away when accelerating

None of the sources consulted explains why an idle noise disappears as the revs rise, so there is no direct diagnosis. Diariomotor suggests pressing the clutch pedal with the car idling: if the vibration reduces or disappears, it points to a worn dual-mass flywheel. Autodoc Club also lists noises that only occur with a cold engine (a ticking from the valves or the "tick" of a manifold leak), so it is worth noting whether it depends on temperature too.^[1][8][9]

What to check first

Pay attention to how it sounds (whistle, roar that changes pitch, rattle, metallic knock, shudder) and when it appears: with the engine cold or warm, at idle, when accelerating hard, above a certain speed or with the steering on full lock. Autodoc Club recommends not ignoring these noises and having the car checked.^[1][2][6]
With the car idling, press the clutch pedal: according to Diariomotor, if the vibrations reduce or disappear, the dual-mass flywheel is worn. RACE warns that the symptoms alone do not confirm it, because they can also come from the clutch, the engine or gearbox mounts, the injection or the ignition.^[3][9]
Have the exhaust inspected over a pit or on a lift: firm mountings, damp patches on the silencer and, if the floor of the cabin gets hot, burnt heat shields.^[2]
Look around the wheels: grease thrown outwards indicates that a CV joint boot has split.^[6]
If the loud metallic noise appears in a relatively new engine, think back to what fuel you have put in: Autodoc Club associates it with detonation from low-octane fuel. If the engine warning light also comes on, ask for a fault code read-out.^[1][10]

Can I keep driving?

Urgency: Garage soon

It depends on the noise. A soft whistle when accelerating can be normal in a turbocharged car, but Autodoc Club recommends not ignoring noises, having the car checked and repairing the affected component. Autofácil considers a metallic noise heard when accelerating serious, because of a badly deteriorated dual-mass flywheel that can end up breaking the gearbox housing; RACE warns that driving without a turbo is dangerous and that a CV joint that seizes at high speed can cause a loss of control. If the noise gets worse, the sensible course is not to prolong the journey and to take the car to a garage.^[1][4][6][7]

How much it costs to fix

Indicative prices published by the sources cited; they depend on the car and the garage.

Repair	Price
Replacing the dual-mass flywheel at an independent garage (according to Diariomotor, 2020; the garage usually bills a minimum of six or eight hours of labour)^[9]	€700 – €1,300
Repairing the dual-mass flywheel depending on the model (removal, refitting and part, according to Autofácil; RACE cites around €1,500 for a complete clutch kit with flywheel, disc, release bearing, slave cylinder, labour and VAT on an average compact car)^[3][4]	€1,000 – €2,000
Replacing a CV joint boot (per wheel, including labour, according to RACE)^[6]	€60 – €120
Replacing the CV joint kit (average garage price, according to RACE, labour not detailed)^[6]	€150 – €300
Replacing the complete driveshaft (indicative quote from RACE, labour not detailed)^[6]	€350 – €700
Repairing a turbo (around €500) or replacing it with a new one (around €1,500), according to RACE; it does not state whether labour is included^[7]	€500 – €1,500
Replacing an engine mount at a garage (around 3-4 hours of work; Autodoc Club cites around €300)^[1]	€300

Documented faults that cause it

Specific engine and gearbox faults, from most to least important (severity × frequency). Below each title, how the symptom shows up in that fault.

- Critical severityFrequency: Common1.6 CRDiMHSG belt tensioner and crankshaft pulley failure (48V mild hybrid)Belt squeal or whistle when accelerating, before any other symptom appears.
Source for the symptom in the 1.6 CRDi^[11]
- Critical severityFrequency: CommonMultitronicWear of the variator chain and conesRattling or metallic noise from the gearbox area, especially when cold or when accelerating.
Source for the symptom in the Multitronic^[12]
- High severityFrequency: Very frequent1.6 HDiTurbo failure through lack of lubrication (carbon deposits and union filter)A high-pitched whistle or siren noise when accelerating.Repair (garage): €700–€1,050
Source for the symptom in the 1.6 HDi^[13]
- High severityFrequency: Common2.0 HDiVariable-geometry turbo failures (actuator, sensors and clogging)Whistling or whining when accelerating.
Source for the symptom in the 2.0 HDi^[14]
- High severityFrequency: Common1.4 T-JetPremature turbocharger failure or wearA high-pitched whistle that rises as you accelerate, reported by several owners before the turbo failed completely.Repair: €1,100–€2,300Appears at around 15,000 km
Source for the symptom in the 1.4 T-Jet^[15]
- High severityFrequency: CommonSkyactiv-DTurbo wear or failure from lack of lubricationA whistle that grows as you accelerate can foreshadow turbo failure, especially if it coincides with oil dilution or consumption.
Source for the symptom in the Skyactiv-D^[16]
- High severityFrequency: Occasional1.6 EcoBoostPremature turbocharger failureA whistle that grows louder when accelerating can warn of play in the turbo before complete failure.
Source for the symptom in the 1.6 EcoBoost^[17]
- High severityFrequency: Occasional1.1 and 1.4 CRDiTurbocharger wear and loss of performanceA growing whistle when accelerating, a sign of play or a leak in the turbo or its hoses.
Source for the symptom in the 1.1 and 1.4 CRDi^[18]
- High severityFrequency: OccasionalMZR-CDTurbocharger wear or failureA whistle that grows louder when accelerating can foreshadow turbo failure, especially if the oil is already diluted or dirty.
Source for the symptom in the MZR-CD^[19]
- High severityFrequency: Occasional1.4 TurboWhistling, loss of power and turbocharger wearNoticeable whistling when accelerating, a sign of bearing wear or leaks in the turbo's intake circuit.Appears at around 75,000 km
Source for the symptom in the 1.4 Turbo^[20]
- High severityFrequency: Occasional2.0 DTI and 2.2 DTISeized or leaking turbochargerA leak at the turbo manifold gasket, like the one documented in a Zafira A, may show up as a whistle or hiss when accelerating.
Source for the symptom in the 2.0 DTI and 2.2 DTI^[21]
- High severityFrequency: Occasional2.2 HDiTurbo faults, somewhat more frequent on the sequential twin-turbo versionsWhistling or whining when accelerating.
Source for the symptom in the 2.2 HDi^[22]
- Medium severityFrequency: Common1.8 TDCiCracked boost hoses and turbo wearA whistle that grows when accelerating when the turbo has play or there is a leak in the hoses.Appears at around 35,000 km
Source for the symptom in the 1.8 TDCi^[23]
- Medium severityFrequency: CommonDSG7 DQ381/DQ500Jerking and juddering when pulling away and at low speedNoises or dull thuds when accelerating hard, and gear changes less smooth than normal.Repair (garage): €1,000–€2,000
Source for the symptom in the DSG7 DQ381/DQ500^[24]
- Low severityFrequency: OccasionalVW 2.0 TFSI EA113Turbo diverter (blow-off) valve failureWhistling when accelerating, loss of boost pressure and weak response.
Source for the symptom in the VW 2.0 TFSI EA113^[25]

Faults elsewhere in the car that cause it

Suspension, brake, electronics and other faults on specific cars, from most to least important.

- Medium severityFrequency: CommonFiat Punto IIPremature clutch wear on the Punto IIThe clutch slips when accelerating, the pedal loses feel or a bearing noise is heard when pressing it.Appears at around 26,000 km
Source for the symptom in the Fiat Punto II^[26]
- Medium severityFrequency: OccasionalMercedes-Benz CLA C117Vibrations and noises from the driveline and differential on the CLA 4Matic and AMGVibrations, noises or jerking under acceleration coming from the rear driveline.
Source for the symptom in the Mercedes-Benz CLA C117^[27]
- Low severityFrequency: OccasionalVolvo C30Wear of the wishbones, ball joints and shock absorbers in the Volvo C30 suspensionNoises or play in the suspension, also when accelerating if the origin is the wheel bearings.
Source for the symptom in the Volvo C30^[28]

Which cars it appears in

These faults affect 15 engines. We have documented 119 models from 19 makes with some of the affected versions: open yours to see all its faults.

Engines

Cars with the affected versions

Abarth

Alfa Romeo

Audi

See all Audi models

Citroën

See all Citroën models

Fiat

Ford

See all Ford models

Hyundai

Jeep

Kia

Lancia

Lancia Delta IIIEngine: 1.4 T-JetYears: 2010–2014

Land Rover

Seat

Škoda

Volkswagen

See all Volkswagen models

Volvo

Noise when accelerating: causes in your car

121 cars have several documented faults that cause this symptom. Choose yours to see only those that affect it, by engine and by year.

Abarth 2

Alfa Romeo 2

Audi 9

Citroën 12

Fiat 7

Ford 12

Hyundai 7

Jeep 2

Kia 7

Lancia 1

Lancia Delta III

Land Rover 2

Mazda 11

Mercedes-Benz 1

Mercedes-Benz CLA C117

MINI 1

MINI Cooper R56

Opel 15

Peugeot 11

Seat 3

Škoda 3

Volkswagen 10

Volvo 3

Noise when accelerating by brand

Frequently asked questions

Is it normal for the car to whistle when accelerating?

A slight whistle when accelerating can be normal in a turbocharged car, according to Autodoc Club. If it is too loud, that source associates it with a leaking hose, and RACE includes whistling from the engine area, together with loss of power, among the symptoms of a faulty turbo.^[1][7]

What noises does a worn dual-mass flywheel make?

The sources cite a rattle or "clack-clack" and a metallic scraping, knocks when starting or switching off the engine and engine vibrations at idle. When it is badly deteriorated, the metallic noise can be heard when accelerating and the fault is serious, according to Autofácil.^[3][4][9]

How much does it cost to replace the dual-mass flywheel?

Diariomotor puts the replacement at between €700 and €1,300 at an independent garage in Spain and close to €2,000 at official dealer services; Autofácil gives €1,000 to €2,000 depending on the model and RACE around €1,500 for a complete clutch kit on an average compact car. The first two figures date from 2020, so it is worth asking for a current quote.^[3][4][9]

How can you tell a CV joint is failing?

RACE describes a shudder through the floor, the seat or the gear lever when accelerating hard or going over 80 km/h, and a "clack-clack" with the steering on full lock at low speed. Grease thrown outwards indicates that the boot has split.^[6]

Could it be the engine mounts?

Yes. Diariomotor explains that with worn mounts, the engine visibly moves when you lift off the accelerator and vibrations are felt more in the cabin. Autodoc Club cites around 3-4 hours of work and around €300 to replace a mount.^[1][5]

Other symptoms: noises

All symptoms

Has this happened to you? Tell us which fault it was, at how many kilometres and how much you paid: it helps other owners know what to expect. Report your fault.

Sources

Every fact on this page links to its source. If you find an error, let us know.

Ruido metálico en el coche durante la aceleración y el ralentíAutodoc Club · Technical documentation · published 20 August 2021 · consulted 4 October 2026 · in Spanish
Razones por las que debes revisar tu sistema de escape — Cómo inspeccionar el sistema de escapeAutodoc Club · Technical documentation · published 28 May 2020 · consulted 4 October 2026 · in Spanish
¿Qué es el volante bimasa del coche y cómo influye en las vibraciones del motor?RACE · Motoring press · published 16 September 2026 · consulted 4 October 2026 · in Spanish
¿Qué síntomas nos dicen que tenemos un problema en el Volante Bimasa?Autofácil · Motoring press · published 5 March 2020 · consulted 4 October 2026 · in Spanish
¿Qué averías pueden provocar unos tacos del motor en mal estado?Diariomotor · Motoring press · published 18 January 2020 · consulted 4 October 2026 · in Spanish
Junta homocinética rota: síntomas y ruidos del cocheRACE · Motoring press · published 29 September 2026 · consulted 4 October 2026 · in Spanish
¿Cuáles son los síntomas de un turbo roto o averiado?RACE · Motoring press · published 23 March 2023 · consulted 4 October 2026 · in Spanish
Colector de escape: funciones, síntomas, parámetrosAutodoc Club · Technical documentation · published 8 October 2020 · consulted 4 October 2026 · in Spanish
Volante bimasa: cómo saber si está averiado y cuánto cuesta sustituirloDiariomotor · Motoring press · published 3 November 2020 · consulted 4 October 2026 · in Spanish
Sensor de detonación: todo lo que necesitas saber sobre sus partes, funcionamiento, tipos y averíasAutodoc Club · Technical documentation · published 22 March 2021 · consulted 4 October 2026 · in Spanish
Kia / Hyundai 1.6 CRDi MHEV Engine FailuresDOHC (especialista en reconstrucción de motores) · Technical documentation · consulted 26 September 2026
Typische Probleme & Haltbarkeit der MultitronicGebrauchtwagenberater · Motoring press · consulted 27 September 2026 · in German
Fallos del turbo 1.6 HDi: cómo evitar que tu motor muera de sedReman Motor Parts · Other source · published 14 August 2025 · consulted 26 September 2026 · in Spanish
Fiabilité du 2.0 HDIFiches-Auto · Motoring press · consulted 27 September 2026 · in French
Fiat 500X : les plus et les moinsFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Fiabilité Mazda CX-5 (2012-2017)Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Fiabilité et pannes Ford S-MaxFiches-auto.fr · Other source · consulted 27 September 2026 · in French
Hyundai i20 I: Typische Probleme & KrankheitenGebrauchtwagenberater · Motoring press · consulted 27 September 2026 · in German
Fiabilité Mazda 6 (2002-2008)Fiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Opel Zafira Tourer : fiabilité, pannes et rappelsFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Fiabilité Opel Zafira - avis et pannes des propriétairesFiches-auto.fr · Owners' forum · consulted 27 September 2026 · in French
Essai, avis et fiabilité des 2,2 HDI 136 chevauxFiches-Auto · Motoring press · consulted 27 September 2026 · in French
Fiabilité et pannes du Ford Focus 2 (1.8 TDCi 115ch)Fiches-auto.fr · Owners' forum · consulted 27 September 2026 · in French
Probleme & Schwachstellen beim DSGGebrauchtwagenberater · Technical documentation · published March 2023 · consulted 27 September 2026 · in German
Common problems of Audi A3 8P 2.0 TFSIEuro Auto Pro · Technical documentation · consulted 5 October 2026
Fiabilité Fiat Punto 2 (1999-2003) : pannes et témoignagesFiches-auto.fr · Other source · consulted 5 October 2026 · in French
Fiabilité Mercedes CLA 2013-2019 (103 témoignages)fiches-auto.fr · Other source · consulted 5 October 2026 · in French
Tous les problèmes sur Volvo C30 2006-2012 (162 témoignages)fiches-auto.fr · Other source · consulted 5 October 2026 · in French