M50 and M52 vs 2.3 MZR DISI Turbo: which engine is more reliable?

According to our risk index, the M50 and M52 carries less risk than the 2.3 MZR DISI Turbo: 52/100 versus 63/100 (both high risk). The M50 and M52 has 2 documented serious faults, the main one being «Cooling system failure (expansion tank, thermostat, pump and radiator)»; the 2.3 MZR DISI Turbo has 2 documented serious faults, the main one being «Timing chain stretch and VVT actuator failure on the 2.3 DISI Turbo».

Risk index

M50 and M52

High risk · 2 serious faults

Lower risk

Risk index

2.3 MZR DISI Turbo

High risk · 2 serious faults

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

Reviewed on 2 November 202614 sources How we work

Is the M50 and M52 reliable?

The M52 and its predecessor the M50 are six-cylinder petrol engines that the sources describe as durable: Enginescope considers 300,000 km routine with the cooling circuit looked after. Watch the plastic cooling parts, VANOS, crankcase ventilation and oil leaks and, in the aluminium-block M52s built from 1995 to March 1998, cylinder wear caused by sulphur (Nikasil).^[1][2][3]

See the 5 of the M50 and M52 faults

Is the 2.3 MZR DISI Turbo reliable?

Mazda's 2.3 DISI Turbo (L3-VDT, 2005-2013) is powerful but demanding: the timing chain, the turbo and oil sludge are its weak points; only buy one with a good oil service history.^[4][5][6]

See the 3 of the 2.3 MZR DISI Turbo faults

Side-by-side comparison

Comparison of M50 and M52 and 2.3 MZR DISI Turbo
Item	M50 and M52	2.3 MZR DISI Turbo
Technical data
Type	Engine	Engine
Fuel	Petrol	Petrol
Displacement	—	2,261 cm³
Timing	Chain	Chain
Power	150–193 hp	256–263 hp
Production	1990–2001^{[7][8][9][10]}	2005–2013^[4][11]
Reliability
Risk index (what is it?)	52High risk	63High risk
Documented faults	5	3
Of high or critical severity	2	2
Worst severity	Critical severity	Critical severity
Main faults	High severity: Cooling system failure (expansion tank, thermostat, pump and radiator) Critical severity: Premature cylinder wear (Nikasil coating) Medium severity: Worn VANOS seals	Critical severity: Timing chain stretch and VVT actuator failure on the 2.3 DISI Turbo High severity: Premature turbocharger wear from poor lubrication on the 2.3 DISI Turbo Medium severity: Oil consumption and sludge in the 2.3 DISI Turbo engine
Most expensive documented repair	No reliable data	up to €2,200Premature turbocharger wear from poor lubrication on the 2.3 DISI TurboPublished figure^[5]
Which versions to buy
BuyRecommended versions	None	None
With cautionVersions to be cautious about	M50B20, 2.0 litre (150 hp; 1990-1995)^[12][13] M50B25, 2.5 litre (192 hp; 1990-1995)^[12][13] M52B20, 2.0 litre (150 hp; 1994-1999)^[8][12] M52B25, 2.5 litre (170 hp; 1995-1999)^[8][12] M52B28, 2.8 litre (193 hp; 1995-1999)^[8][12][14] M52TUB20, 2.0 litre (150 hp; 1998-2001)^[7][12] M52TUB25, 2.5 litre (170 hp; 1998-2000)^[7][12] M52TUB28, 2.8 litre (193 hp; 1998-2001)^[3][7][12]	2.3 MZR DISI Turbo 256-260 hp (L3-VDT, 2005-2009)^[4][5] 2.3 MZR DISI Turbo (L3-VDT, 2010-2013)^[4][5]
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

M50 and M52

2.3 MZR DISI Turbo

Other comparisons

With the M50 and M52

With the 2.3 MZR DISI Turbo

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Sources

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

BMW 3 Series E36 320i (M52B20): reliabilityEnginescope · Other source · consulted 2 November 2026
BMW M52 reliabilityAutoscore · Other source · consulted 2 November 2026
BMW M52 Engine: Performance, Reliability, and TuningBMWBlog · Motoring press · consulted 2 November 2026
Mazda L engineWikipedia (inglés) · Other source · consulted 5 October 2026
Problemas Mazda CX-7Totalrenting · Other source · consulted 5 October 2026 · in Spanish
2009 Mazda CX-7 engine problemsCarComplaints · Owners' forum · consulted 5 October 2026
BMW M52Wikipedia (inglés) · Other source · consulted 2 November 2026
BMW M52Wikipedia (alemán) · Other source · consulted 2 November 2026 · in German
BMW M50Wikipedia (inglés) · Other source · consulted 2 November 2026
BMW M50Wikipedia (alemán) · Other source · consulted 2 November 2026 · in German
Mazda CX-7Wikipedia (inglés) · Other source · consulted 5 October 2026
BMW M50 / M52: problemas conocidosEnginescope · Other source · consulted 2 November 2026
Der BMW M50 Motor: Technische Daten, Probleme, Haltbarkeit & FahrzeuglisteCarWiki.de · Other source · consulted 2 November 2026 · in German
BMW Z3 Reliability Guide: Everything You Need to Know Before BuyingEuro Premium Parts · Technical documentation · consulted 2 November 2026