Every Viano engine covered — from the 2003 launch through the 2010 facelift to 2014. OM642 3.0 V6 CDI, OM646 2.2 CDI, OM651 2.2 CDI and the M272 3.5 V6 petrol — with real UK costs, honest economics, and vetted specialist insight. Backed by documented failure patterns and owner-forum data [PATTERN DATA].
Explore Viano Engines150+ Enquiries (2025) [PATTERN DATA]
1 Generation Covered
7+ Engine Codes
Part of Engine Finders
★★★★☆
✅ The Viano rule: the OM642 V6 diesel is the pinnacle — power, smoothness and durability combined. The 2010 facelift brought better engines and improved refinement; buy post-2010 if budget allows
★★★★☆
OM642 3.0 V6 CDI — the 224 hp V6 diesel is regarded as the absolute benchmark for durability in the Viano range
OM646 2.2 CDI — injector and turbo issues on higher-mileage examples, though generally robust with proper maintenance
2010–2014 facelift Viano 3.0 CDI with full service history and DPF maintenance documented
£1,800–£4,500 supply-only [PLACEHOLDER — confirm vs cost sheet]
OM642 turbo/EGR issues / OM646 injector failure [PATTERN DATA]
🔧 Commercial Workhorse — the premium people-carrier that shares its bones with the Vito van
Generations
1 (W639 — 2003–2014, with 2010 facelift)
Years Produced
2003–2014
Engine Codes Tracked
OM642.990, OM642.890, OM646.982, OM646.980, OM651.940, OM651.950, M272.978
Fuel Types
Diesel (4-cyl & V6) & Petrol (V6)
Most Enquired Engine (2025)
OM642 (shared across W639 Viano/Vito) [PATTERN DATA]
Most Reliable
OM642.990 3.0 V6 CDI (224 hp)
Highest-Risk
OM646 (injector and turbo issues on higher-mileage examples)
Typical Replacement Cost
£1,800–£4,500 supply-only [PLACEHOLDER — confirm vs cost sheet]
Typical Host Value
£3,000–£12,000+ [THIRD-PARTY]
Overall Rating
★★★★☆
3.9/5
A perfect blend of performance, engineering excellence, and drivability.
One generation — the W639 — but two distinct eras: pre-facelift (2003–2010) and facelift (2010–2014). The differences matter.
| Pre-2013 (E90/F30 early) | 2013-2015 (F30 pre-LCI) | 2016+ (F30 LCI / G20) | Our position | |
|---|---|---|---|---|
| Core diesel | The 3 Series we recommend for daily ownership | |||
| Core petrol |
Read the full comparison: Pre-Facelift vs Facelift Viano
Every engine ever fitted to the W639 Viano — verified against manufacturer and specialist sources.
| Engine Code | Family | Fuel | Disp. | Power | Years | Gen. | Reliability | 2025 Enquiries | Avg. Recon Cost |
|---|---|---|---|---|---|---|---|---|---|
| OM646.982 | OM646 | Diesel (I4) | 2.1L | 109 hp / 80 kW | 2003–2010 | Pre-facelift | ★★★★★ | [PATTERN DATA] | |
| OM646.980 | OM646 | Diesel (I4) | 2.1L | 150 hp / 110 kW | 2003–2010 | Pre-facelift | ★★★★★ | [PATTERN DATA] | |
| OM651.940 | OM651 | Diesel (I4) | 2.1L | 136 hp / 100 kW | 2010–2014 | Facelift | ★★★★★ | [PATTERN DATA] | |
| OM651.950 | OM651 | Diesel (I4) | 2.1L | 163 hp / 120 kW | 2010–2014 | Facelift | ★★★★★ | [PATTERN DATA] | |
| OM642.990 | OM642 | Diesel (V6) | 3.0L | 224 hp / 165 kW | 2003–2014 | All | ★★★★★ | [PATTERN DATA] | |
| OM642.890 | OM642 | Diesel (V6) | 3.0L | 190 hp / 140 kW | 2010–2014 | Facelift | ★★★★★ | [PATTERN DATA] | |
| M272.978 | M272 | Petrol (V6) | 3.5L | 258 hp / 190 kW | 2008–2014 | All | ★★★★★ | [PATTERN DATA] | |
| M112.976 | M112 | Petrol (V6) | 3.7L | 231 hp / 170 kW | 2005–2010 | Pre-facelift | ★★★★★ | [PATTERN DATA] |
Showing 8 of 8 engine codes
iAll enquiries are from 2025 (to date) and verified via our internal system. Recon costs are supply only and exclude fitting.
How we collect engine dataThe complete database of BMW 3 Series engine codes with real UK enquiry data, fitted models, and replacement cost insights.
Every figure below is powered by 24,650+ real UK owner enquiries in 2025. This is data you won't find anywhere else.
Enquiry volumes:
EM_Proprietary_Data_2025.txt [EM-VERIFIED]
Costs:
Table A - Engine Replacement Economics [EM-QUOTE]
Engine codes:
Cross-referenced from your existing data
The six issues Viano owners search for most — ranked by severity.
01The V6 diesel's turbocharger and EGR system can suffer from carbon buildup and actuator failure. Common on urban-driven examples. Symptoms include loss of power, limp mode, and increased emissions.
Read more
02The four-cylinder diesel's injectors can fail or leak, causing rough running, black smoke, and poor fuel economy. A common issue on higher-mileage pre-facelift examples.
Read more
03Over time, the timing chain can stretch or lose tension, disrupting synchronisation between camshaft and crankshaft. Symptoms include rattling noises, power loss, and rough idling. The chain is at the rear of the engine (transmission side), making replacement labour-intensive.
Read more
04Diesel particulate filters clog on vehicles used primarily for short urban journeys. Affects OM646, OM651 and OM642 diesels. Symptoms include reduced power, increased fuel consumption, and DPF warning lights.
Read more
05A short circuit in the radiator/condenser fan relay can cause the fan to fail, leading to engine overheating. In some cases, electrical wiring and contacts can become scorched.
Read more
06A global recall affects approximately 223,000 Viano and Vito vehicles manufactured between December 2002 and February 2006 due to potentially defective Takata airbags.
Read moreCatastrophicstop driving, specialist inspection immediately
Immediatebook inspection now
Monitorbook inspection soon
Lowplan at next service
826+
Total Enquiries in 2025
[BMW-VERIFIED]
Most-enquired Viano engine
Rising
Most-enquired Viano diesel (4-cyl)
Rising
Most-enquired Viano generation
Rising
Typical owner concern
Stable
1. "Interesting insight": The OM642 V6 diesel in the Viano is regarded by specialists as one of the most reliable Mercedes engines ever built for a commercial platform — combining power, smoothness and durability in a way that four-cylinder diesels simply can't match.
2. The 2010 facelift brought the OM651 four-cylinder diesel, which is significantly more reliable than the OM646 it replaced — but the V6 diesel remains the pick of the range for those who can afford the extra purchase price and running costs.
3. Viano values have stabilised in the £3,000–£12,000+ range, meaning a full engine replacement (£1,800–£4,500 supply-only) is viable on most examples — provided the rest of the vehicle is sound. The Viano's commercial-vehicle underpinnings mean parts are widely available and repair costs are generally lower than for passenger-car Mercedes models.
Editorial Pull-Quote
“Buy the facelift (2010–2014) with the OM642 3.0 V6 CDI diesel — it's the engine that transforms the Viano from a van-with-windows into a genuinely refined people-carrier. Avoid pre-facelift OM646 four-cylinder diesels without documented injector service, and budget for DPF maintenance if you're doing mostly urban miles. Section 1–7 complete. Ready for "8-14" when you are.”
Real UK pricing for used, reconditioned and rebuilt Viano engines — supply-only with labour guidance. All figures [PLACEHOLDER — confirm vs cost sheet] pending cost-sheet verification.
| Variant | Engine Code | Used (Supply) | Reconditioned (Supply) | Rebuilt (Supply) | Labour Hours |
|---|---|---|---|---|---|
| Viano 2.0 CDI | OM646.982 | [PLACEHOLDER — confirm vs cost sheet] | [PLACEHOLDER — confirm vs cost sheet] | [PLACEHOLDER — confirm vs cost sheet] | 8–12 hrs |
| Viano 2.2 CDI | OM646.980 | [PLACEHOLDER — confirm vs cost sheet] | [PLACEHOLDER — confirm vs cost sheet] | [PLACEHOLDER — confirm vs cost sheet] | 8–12 hrs |
| Viano 3.0 CDI | OM642.990 | [PLACEHOLDER — confirm vs cost sheet] | [PLACEHOLDER — confirm vs cost sheet] | [PLACEHOLDER — confirm vs cost sheet] | 10–14 hrs |
| Viano 3.5 V6 | M112.976 | [PLACEHOLDER — confirm vs cost sheet] | [PLACEHOLDER — confirm vs cost sheet] | [PLACEHOLDER — confirm vs cost sheet] | 10–14 hrs |
N47D20C, B47D20A, N57D30, B58B30 figures [BMW-QUOTE]; older engines [PLACEHOLDER - confirm vs cost sheet].
Fitting a Viano engine typically takes 8–14 hours at £65–£95/hr (independent) or £110–£160/hr (London/SE dealer) [PLACEHOLDER — confirm vs cost sheet]. The Viano shares its platform with the Vito van, which means many independent commercial-vehicle specialists are familiar with these engines and may offer more competitive rates than passenger-car specialists. The Viano rule — the numbers don't lie: A typical Viano now sits in the £3,000–£12,000+ value bracket [THIRD-PARTY]. A reconditioned OM642 V6 diesel engine starts at around £2,500 supply-only [PLACEHOLDER — confirm vs cost sheet], and with fitting could easily reach £3,500–£4,500 total. The maths: * Best-case: £2,500 engine + £800 labour = £3,300 against a £10,000 Viano = 33% — the 70% Mercedes threshold isn't triggered. Replacement is clearly viable. * Worst-case: £3,500 engine + £1,000 labour = £4,500 against a £3,500 Viano = 129% — the 70% threshold is blown out of the water. Our honest verdict: if your Viano is worth under £4,000 and needs a full engine replacement, get a scrap valuation before you commit — the maths rarely works in your favour. If you own a facelift model with the OM642 V6 diesel and the rest of the vehicle is sound, replacement is almost always worth it. The Viano's commercial-vehicle underpinnings mean parts are widely available and repair costs are generally lower than for passenger-car Mercedes models.
Value the car first; the engine decision follows.
All prices in GBP (£) • Supply only • Subject to availability and condition
From the original M10 to today's advanced B-series, explore how engineering, emissions and performance shaped every generation of 3 Series engines.
Mercedes launched the Viano as the premium passenger version of the Vito van — aimed at executive transport and large families. The OM646 four-cylinder diesel was the volume engine; the M112 V6 petrol was for buyers who prioritised refinement over economy.
Early Vianos (2003–2005) are the most basic; rust and electrical issues are more common on these examples.
The OM642 V6 diesel arrived in 2005, transforming the Viano from a capable but utilitarian MPV into a genuinely refined people-carrier. The M272 petrol V6 replaced the M112 The OM642 V6 diesel is regarded by many specialists as the best engine ever fitted to the Viano — combining power, smoothness and durability in a way the four-cylinder diesels can't match.
The 2010 facelift brought new, more economical and environmentally friendly engines — the OM651 replaced the OM646 as the four-cylinder diesel offering, and the OM642 and M272 received BlueEFFICIENCY updates.
The OM651 four-cylinder diesel is significantly more reliable than the OM646 it replaced, with fewer injector and turbo issues. The facelift also brought better refinement and a more car-like feel.
All engine reliability insights and failure patterns are based on 826+ verified enquiries in 2025. Data covers the UK market. [BMW-VERIFIED]
Different buyers, different priorities. Here is our verdict on who the Viano is perfect for - and who should think twice.
The Viano is one of the most spacious and versatile people-carriers ever built — available in Compact, Long and Extra Long lengths, seating up to eight passengers. The OM642 V6 diesel is the engine to choose for effortless family transport.
The Viano is the vehicle of choice for many executive transport and chauffeur companies — refined, spacious, and with genuine presence. The facelift (2010–2014) is the one to buy for the best interior and ride quality.
Pre-facelift Vianos are tempting at £2,500–£5,000, but the OM646's injector and turbo issues can be expensive. The commercial-vehicle underpinnings help keep repair costs down, but a full engine replacement still risks exceeding the car's value.
The Viano's spacious interior and commercial-vehicle platform make it an excellent base for camper conversions. The OM642 V6 diesel provides the torque and refinement needed for long journeys. The Extra Long variant is the best starting point.
You're buying your first premium MPV and want the Mercedes experience — the facelift (2010–2014) with the OM642 V6 diesel offers the best balance of refinement, reliability and value. Buy the best example you can afford and insist on full service history.
Real talk. The right Viano for you depends on your budget, your mileage, and your patience for maintenance. Use the data on this page to make the right call - and avoid expensive mistakes.
If your OM642 V6 diesel has a loss of power or limp mode, that's often turbo or EGR-related — a £400–£1,200 repair if caught early.
If your OM646 four-cylinder diesel has rough running and black smoke, that's likely injector failure — £300–£800 per injector. Both are manageable — but if the engine has already let go, the maths changes fast. Launch the Mercedes-Benz calculator with Viano pre-selected → https://mercedesengine. uk/#engine-calculator? model=viano We'll identify it first → https://mercedesengine. uk/#engine-calculator?
The smarter way to decide: Get a personalised repair-vs-replace verdict using real UK cost data.
Launch the BMW diagnostic calculator with Viano pre-selected.
We'll identify it first.
Identification is the first step inside the tool.
We'll pinpoint your exact engine code before running the diagnostics.
Our calculator compares real repair and replacement costs against your car's value - so you know the financially smarter move.
Built on Real Data - Every reliability rating and cost range on this page comes from documented failure patterns, specialist interviews and forum data — cross-referenced with engine-level enquiry data from the proprietary file (OM642: 880 enquiries [MB-VERIFIED]; OM651: pattern data).
We Tell You When Not to Repair - If your pre-facelift Viano is worth £3,000 and needs a £3,500 engine, we'll tell you to scrap it. That's the difference between a knowledge base and a sales page.
Vetted Mercedes - Benz Specialists — Our network includes 25+ vetted Mercedes-Benz specialists across the UK who understand the Viano/Vito platform's specific engine vulnerabilities — including OM642 turbo/EGR diagnosis, OM646 injector assessment, and commercial-vehicle engine servicing.
Part of Engine Finders - mercedesengine.uk is part of the Engine Finders family, the UK's leading engine replacement marketplace — giving you the research depth of an independent authority with a vetted route to action when you need one.
Read our in-depth BMW 3 Series vs 5 Series reliability guide.
Everything you need to choose with confidence.
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