Car Model Guide/ Mercedes-Benz/ E-Class/ S212/ E 250 CDI

E 250 CDI OM651

The four-cylinder diesel that carried Mercedes for a decade. Durable bottom end; the money is in the injectors, and early piezo units are the reason some of these cars are cheap.

Overview

The E 250 CDI is the OM651 diesel version of the Mercedes-Benz E-Class wagon (S212), sold 2009–2016 with 204 PS and auto_7g. Demands diligence at level 3. The twin-turbo OM651 is quick and frugal, with the same early chain and injector faults as the rest of the family. 18 failure modes are recorded against its engine, gearbox, chassis and shared components. Prices on this page are illustrative placeholders rather than a sourced market sample. See the methodology for how the bands are derived.

Mercedes-Benz E-Class wagon (S212) · photo Mercedes-Benz E 350 CGi Estate (4979954100) by nakhon100 · CC BY 2.0 · Wikimedia Commons

Power204 PS

Torque500 Nm

Years2009–2016

Fueldiesel

DriveRWD / 4MATIC

EnginesOM651

Biggest risks

Ranked by probability × repair cost. 18 recorded in total.

52Demands diligence

Piezo injector failure (early OM651)€1,200–€2,400partly checkable
Timing chain and sprocket wear (early OM651)€900–€2,500partly checkable
DPF clogging and forced regeneration€250–€1,800partly checkable

Risk level −22 · Likely spend vs price −26 · all issues →

System by system9 systems reviewed · 1 with no recurring fault reported

Engine⚠ attentionTiming chain and sprocket wear (early OM651), €900–€2,500.

Fuel system⚠ attentionPiezo injector failure (early OM651), €1,200–€2,400.

Intake & air✓ clearNo recurring fault reported for this system on this engine.

CoolingwatchCoolant expansion tank cracking, €120–€250.

Emissions⚠ attentionDPF clogging and forced regeneration, €250–€1,800.+1 more in this system

Transmissionwatch7G-Tronic conductor plate and 13-pin connector leak (722.9), €400–€900.+1 more in this system

ElectricswatchElectronic steering lock (ESL/ELV) failure, €150–€1,200.+3 more in this system

Suspension & brakeswatchFront control arm bushing wear, €300–€700.+4 more in this system

Body & interiorwatchCorrosion at the rear subframe and arch seams, €300–€2,000.+1 more in this system

Pre-facelift or facelift, this engine spans both

The same badge either side of the changeover. Bands are split at the facelift year from the generation record.

Phase	Years	Low	Average	High	Good buy	What differs
pre Pre-facelift	2009–2012	€5,900	€9,450	€15,750	€7,700	The specification the car launched with.
LCI Facelift (LCI)	2013–2016	€6,400	€10,300	€17,150	€8,350	Single-piece headlamps; new bonnet and bumpers; M274 replaced the M271 EVO petrol four; M276 replaced the M272 V6; Diesels migrated from CDI to BlueTEC

Known issues, ranked by expected cost

Faults recorded against this engine, its components and its chassis, ranked by likelihood × repair cost. Costs are indicative ranges with a stated labour basis.

Piezo injector failure (early OM651)OM651 2.1 CDI€1,200–€2,400

Hard starting, rattle at idle, smoke, poor running and injector codes; sometimes fuel dilution in the oil. First-generation piezo injectors fail and can leak into the cylinder. Later production moved to a revised solenoid injector.

Check: Cold start and listen for an uneven rattle; scan for injector correction values, which a specialist can read and interpret. Ask which injectors are fitted. A receipt naming the revised part is worth real money on these cars.

Later parts: Revised injectors on later production

FuelcommonPartly detectableevidence: documented100–200k km

Timing chain and sprocket wear (early OM651)OM651 2.1 CDI€900–€2,500

A rattle or whirr from the front of the engine for two or three seconds on cold start; at worst the chain jumps teeth and bends valves. The early oil-fed tensioner and camshaft sprocket design on pre-2012 OM651 engines wears; Mercedes revised the sprockets, tensioner and cover for later cars. Extended oil intervals and low oil level make it worse.

Check: Listen at a genuinely cold start on any pre-2012 car for a front-of-engine rattle, and favour a car with the revised sprockets or documented chain work.

Later parts: Revised sprockets, tensioner and cover from around 2012

EnginecommonPartly detectableevidence: documented90–180k km

DPF clogging and forced regenerationDPF€250–€1,800

Warning light, limp mode, oil level rising above the maximum mark from fuel dilution. The filter needs sustained hot running to regenerate. A car used for short urban trips never completes a regeneration cycle.

Check: Read the DPF soot load and the distance since the last regeneration on a scan tool, and check the engine oil level and smell it for diesel. Ask what the car was used for. A short-trip city diesel is the wrong car regardless of mileage.

EmissionscommonPartly detectableevidence: documented120–250k km

Front control arm bushing wearE9x chassis€300–€700

Knocking over bad surfaces, vague or wandering steering, uneven front tyre wear, steering shimmy under braking. The front lower arm bushings are a known wear item on this chassis and go well before the ball joints.

Check: Drive over a rough road at low speed with the windows down and listen. Check the inside edges of the front tyres for feathering.

SuspensionuniversalDetectable at viewingevidence: documented80–150k km

Electronic steering lock (ESL/ELV) failureE-Class platform€150–€1,200

The engine cranks but won't start and the steering stays locked, sometimes after several attempts, with steering-lock fault codes. The small motor that drives the locking bolt wears out and the module eventually blocks further attempts. The cause is consistent motor wear rather than anything variable.

Check: Do several cold starts. Listen for the steering-lock clunk as the key goes in, and scan for B2254 and related codes; intermittent no-starts are the early warning.

ElectricalcommonPartly detectableevidence: documented80–200k km

7G-Tronic conductor plate and 13-pin connector leak (722.9)7G-TRONIC€400–€900

Harsh, delayed or jerky shifts, holding a gear then banging the next in, and limp mode, often with speed-sensor or gear-ratio fault codes. The speed sensors in the conductor plate (mechatronic) fail, and/or the external 13-pin connector leaks fluid that wicks up the wiring into the control unit. Early units are the most affected.

Check: Test-drive through every gear cold and warm. Scan the transmission, and pull the external 13-pin plug to check for fluid on the pins.

TransmissioncommonPartly detectableevidence: documented120–220k km

Rear self-levelling air-suspension leak (estate)S212 body€400–€900

The rear sits low or sags overnight, a suspension-malfunction message, and a compressor that runs long or fails. The rear air springs perish and leak, the air lines chafe, or the compressor wears. The S212 estate has rear self-levelling air suspension as standard, so every one of them ages into this.

Check: Park it level overnight and check the rear ride height and for warning messages the next morning; inspect the airbags and lines for cracks and a long-running compressor.

SuspensioncommonDetectable at viewingevidence: documented100–200k km

Run-flat tyres and kerbed or cracked wheelsE9x chassis€150–€900

Harsh ride, vibration at speed, slow punctures. Stiff-sidewall run-flats transmit impacts straight into the rim, and these alloys crack rather than bend.

Check: Inspect the inner rim edge of every wheel for cracks and hairline splits, not just the face for kerbing. Budget for a set of conventional tyres; most owners switch and the ride improves markedly.

SuspensioncommonDetectable at viewingevidence: documented

Ranked by probability × repair cost, not by how loudly a failure is discussed. Inherited from the engine, gearbox, chassis and shared components, each written once. All 18 issues in full →

Mileage and servicing

What the odometer does and doesn't tell you here, plus the service items whose neglect causes the expensive failures above.

The extra performance doesn't change the checklist. Then scan a pre-2012 car for chain and injector faults before anything else.

Service item	Interval	Cost
Engine oil Chain and injector wear track oil condition	on time, correct spec	€120–180
Timing chain check A worn chain can jump	listen at cold start on pre-2012 cars	free to assess
Injector scan Delphi piezo injectors are a known early fault	on purchase	free to assess

What to pay

What this engine sells for, against the median of every engine in the chassis. All figures are illustrative placeholders. See the basis chips.

median €9.9k

€5.9k€7.7k€17.1k

Cheapfind the reasonGood buyif it checks outFairnormal moneyOverpricedneeds justifying

Asking price (€)Mileage (km)

Enter an asking price to get a verdict against this variant's band: cheap, fair, good buy or overpriced.

United States vs Europe

1 EUR = 1.08 USD · 2026-07

🇪🇺 Europe · EUR€7,700band €5,900–€17,150

🇺🇸 United StatesNot soldE 250 CDI OM651 was never a US-market car

What that meansNo US band exists to compare. Any car you find there's a private import, parts and specialist knowledge are thinner, and the price says more about import cost than about the market.

US figures are the EU band converted at a stated rate. No US market differential is modelled: we hold no sourced US asking prices, and inventing one would be worse than saying so. What the comparison does show for real is availability. Most of this range was never sold in the US.

ModelMercedes-Benz E-Class E 250 CDI
ChassisS212
EngineOM651
Years2009–2016
MarketCentral EU
Windowrolling 12 months to 2026-07

Good buy at or under the marker · Median asking price · bar spans the 10th to 90th percentile · dashed line is the s212 median, all 10 engines

Good buy isn't the same as cheapest. The good-buy figure assumes the known failure items are either done with receipts or verifiably not yet due. Full breakdown by facelift phase →

Buyer notes

Our judgement, kept separate from the records it's built on.

Our read, not a record

The E 250 CDI is the sweet spot for anyone who finds the E 220 a little slow. The twin-turbo OM651 makes 204 PS and 500 Nm, enough to shift a big saloon briskly, on almost the same fuel as the lesser diesels. It shares their early-engine faults and their fixes, so the buying process is the same: favour a later car or a documented earlier one, and check for 4MATIC where fitted. It's the most car for the money among the four-cylinder diesels.

Everything above this line comes from the issue and specification records. This paragraph is our judgement on top of them. See how we reach it.

Full specification

Manufacturer figures for this engine and body, as recorded in the variant and engine data.

Engine code	OM651 2.1 CDI
Configuration	I4, turbocharged · 2143 cc
Fuel / injection	diesel · common rail
Model years	2009–2016
Facelift phase	Sold either side of the 2013 facelift, 2009–2012 pre, 2013–2016 LCI
Power / torque	204 PS · 500 Nm
Transmissions	7-speed automatic (7G-Tronic)
Gearbox families	7G-TRONIC
Drivetrain	RWD · 4MATIC
Economy (real-world)	4.7–6.2 l/100 km mixed
Markets	EU

E 250 CDI OM651

Overview

Pre-facelift or facelift, this engine spans both

Known issues, ranked by expected cost

Pre-purchase inspection

1Cold startYou get one. If the engine is warm when you arrive, come back another day.

2Static checksEngine off, ideally on a lift.

3On the driveInclude low-speed manoeuvring, not just an open road.

4PaperworkOn these cars the folder is most of the value.

5OBD scanMandatory. A seller who refuses a scan has answered the question.