2.2 CDI (OM646) vs 2.2 MultiJet / BlueHDi (Stellantis): which engine is more reliable?

According to our risk index, the 2.2 MultiJet / BlueHDi (Stellantis) carries less risk than the 2.2 CDI (OM646): 14/100 (low risk) versus 46/100 (moderate risk). The 2.2 CDI (OM646) has 1 documented serious fault, the main one being «Injector seal leak with carbonisation around the seat»; the 2.2 MultiJet / BlueHDi (Stellantis) has 1 documented serious fault, the main one being «Unvulcanised fuel return pipe: fuel leak and fire risk».

Risk index

2.2 CDI (OM646)

Moderate risk · 1 serious fault

Risk index

2.2 MultiJet / BlueHDi (Stellantis)

Low risk · 1 serious fault

Lower risk

The index (0–100) weights the severity and frequency of the three most serious documented faults. How it is calculated

Reviewed on 30 October 202621 sources How we work

Is the 2.2 CDI (OM646) reliable?

The OM646 is the 2.2 CDI four-cylinder diesel that Mercedes-Benz fitted between 2002 and 2010 to the C-Class, E-Class, Vito/Viano and Sprinter, as the successor to the OM611 (1998-2006). It is a fundamentally sound engine, considered robust in its mechanical base, but with known and well-documented faults: leaks at the injector seals, a clogged EGR valve, particulate filter sensor failures and a short-lived water pump on some versions.^[1][2][3][4]

See the 6 of the 2.2 CDI (OM646) faults

Is the 2.2 MultiJet / BlueHDi (Stellantis) reliable?

The 2.2 diesels of Stellantis's large vans (BlueHDi DW12 in the Boxer, Jumper and Movano; Multijet 3 in the Ducato) are recent engines with no fault statistics of their own. What is documented are campaigns: AdBlue and SCR software, and the fuel return pipe on 2024-2025 units, with a fire risk. Long-term history is missing.^{[5][6][7][8][9]}

See the 2 of the 2.2 MultiJet / BlueHDi (Stellantis) faults

Side-by-side comparison

Comparison of 2.2 CDI (OM646) and 2.2 MultiJet / BlueHDi (Stellantis)
Item	2.2 CDI (OM646)	2.2 MultiJet / BlueHDi (Stellantis)
Technical data
Type	Engine	Engine
Fuel	Diesel	Diesel
Displacement	2,148 cm³	—
Timing	Chain	Timing belt (dry)
Power	82–170 hp	120–180 hp
Production	1998–2010^[1][10][11]	since 2019^{[12][13][14][15]}
Reliability
Risk index (what is it?)	46Moderate risk	14Low risk
Documented faults	6	2
Of high or critical severity	1	1
Worst severity	High severity	High severity
Main faults	High severity: Injector seal leak with carbonisation around the seat Medium severity: EGR valve clogged or seized by soot Medium severity: Leak and premature failure of the water pump	High severity: Unvulcanised fuel return pipe: fuel leak and fire risk Low severity: AdBlue (SCR) system: the warning light may not come on if the urea doser fails
Most expensive documented repair	up to €300Faulty air flow meter on the 220 CDI (OM 611 and OM 646)Published figure^[16]	No reliable data
Which versions to buy
BuyRecommended versions	None	None
With cautionVersions to be cautious about	OM611 (predecessor, 2.2 CDI, 1998-2006)^[2][4] OM646 pre-EVO (2002-2007, Euro 3/4, 88-150 hp)^[2][3][4] OM646 EVO (2006-2009, up to 170 hp)^[4]	2.2 BlueHDi 120/140/165 (DW12 RU, Euro 6d, Boxer and Jumper 2019-2023, Movano C 2021-2023)^{[6][17][18][19]} 2.2 Multijet 3 H3-Power 120/140/160/180 (Ducato, Euro 6d-Final, 2021-2023)^[5][20][21] 2.2 Multijet Euro 6e 120/140/160/180 (Ducato, Boxer, Jumper, Movano C and Proace Max, 2024 onwards)^[7][8][9]
AvoidVersions to avoid	None	None

Severity of each fault: green, low; amber, medium; red, high; dark red, critical. How we rate them

Cars that each one is fitted to

2.2 CDI (OM646)

2.2 MultiJet / BlueHDi (Stellantis)

Other comparisons

With the 2.2 CDI (OM646)

With the 2.2 MultiJet / BlueHDi (Stellantis)

Compare other engines

First engine

Second engine

That is the comparison you are viewing: change one of the two engines.

Sources

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

Mercedes-Benz OM 646/OM 647/OM 648Wikipedia (alemán) · Other source · consulted 27 September 2026 · in German
Mercedes C-Klasse W203 – Typische Probleme & SchwachstellenGebrauchtwagenberater · Motoring press · consulted 27 September 2026 · in German
Fiabilité 200 CDI MercedesFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Fiabilité 220 CDIFiches-auto.fr · Motoring press · consulted 27 September 2026 · in French
Fiat Ducato 2.3 Multijet 2026: Probleme, Zahnriemen, Varianten (nota sobre el 2.2 Multijet 3)PlanMyCamper · Other source · consulted 9 October 2026 · in German
Boxer: error de software del inyector de urea (alerta Safety Gate A12/01870/23)RappelConso (Gobierno de Francia) · Official body · published 25 August 2023 · consulted 9 October 2026 · in French
Ducato NG: tubo de retorno de combustible (alerta Safety Gate SR/00527/26)RappelConso (Gobierno de Francia) · Official body · published 20 February 2026 · consulted 9 October 2026 · in French
Rückruf Stellantis: Diese Transporter können Kraftstoff verlierenAuto Motor und Sport · Motoring press · published 4 March 2026 · consulted 9 October 2026 · in German
Stellantis. Risque de fuite de carburant sur les véhicules utilitairesL'Argus · Motoring press · published 12 March 2026 · consulted 9 October 2026 · in French
Mercedes-Benz OM646 engineWikipedia · Other source · consulted 27 September 2026
Mercedes-Benz OM611 engineWikipedia · Other source · consulted 27 September 2026
PSA EW/DW engine (sección DW12 y DW12 RU)Wikipedia (inglés) · Other source · consulted 9 October 2026
Fiat Ducato (motores Euro 6d-Temp, 6d-Final y 6e)Wikipedia (alemán) · Other source · consulted 9 October 2026 · in German
Atención a la junta de culata del motor 2.2 de la Fiat Ducato y equivalentesAutopos · Motoring press · published 15 July 2026 · consulted 9 October 2026 · in Spanish
Opel Movano (Movano C desde 2021)Wikipedia (alemán) · Other source · consulted 9 October 2026 · in German
Caudalímetro o sensor MAF: qué es, cómo funciona y cuáles son las averías más frecuentesDiariomotor · Motoring press · consulted 30 October 2026 · in Spanish
Jumper: error de software del inyector de urea (alerta Safety Gate A12/01876/23)RappelConso (Gobierno de Francia) · Official body · published 25 August 2023 · consulted 9 October 2026 · in French
Movano: error de software del inyector de urea (alerta Safety Gate A12/01877/23)RappelConso (Gobierno de Francia) · Official body · published 25 August 2023 · consulted 9 October 2026 · in French
DVSA – base de llamadas a revisiónDVSA (Reino Unido) · Official body · consulted 9 October 2026
ADAC Pannenstatistik 2026 (categoría Vans/Transporter)ADAC · Reliability study · published 23 April 2026 · consulted 9 October 2026 · in German
Fiat Ducato 2015-2025 Maintenance Plans (2.2 H3-Power)Haynes (Reino Unido) · Technical documentation · consulted 9 October 2026