Why it's a good car
The 2014 E350 is the W212 facelift, and it has the right engine: the M276 3.5-liter V6 (about 302 hp) that replaced the earlier M272, whose balance-shaft defect ate engines from the inside. It is paired with the 722.9 7G-Tronic Plus seven-speed automatic and was built as a genuine long-distance car — high highway mileage is not the alarm it first appears to be. And on the North American rear-wheel-drive E350 sedan, the suspension is conventional steel springs, not the expensive air suspension fitted to some other E-Class variants — so there is no air-strut bill lurking on this specific car.
Does it have a timing belt or a timing chain?
A timing chain. The M276 is chain-driven, so there is no belt to replace. The thing to listen for instead is a brief rattle from the camshaft-adjuster and timing-chain area on a cold start; a clean, quiet cold start is exactly what you want.
The things to check before you buy
- Cold-start rattle With the engine stone cold, listen at the front for the first few seconds. A quick settle is normal; a sustained metallic rattle points to worn camshaft adjusters.
- Engine wiring harness / cam-sensor oil intrusion The camshaft-position-sensor seals on this engine can seep oil that wicks along the harness toward the ECU. Caught early it is a seal-and-clean job; ignored, it can destroy the harness and computer and become the most expensive failure on the car. Have a mechanic look at the connectors with the engine cover off — this is non-negotiable.
- Transmission behavior The 722.9 conductor plate (its electronic valve-body brain) is a known wear item. You want clean shifts cold and warm — no harsh 1–2, no long delay engaging Drive, no limp mode.
- Proper diagnostics These need a Mercedes-capable scan tool, not just a generic reader, to see the transmission and SRS systems where the real faults hide.
- Ordinary age items The plastic coolant expansion tank cracks with age, spark plugs come due, and blower regulators and rear shock mounts are common nuisance items.
Open recalls — check the VIN, it’s free
Recalls are VIN-specific — you cannot assume the status from the model year. Look up any 2014 Mercedes-Benz E350’s open recalls free by VIN at the U.S. National Highway Traffic Safety Administration (NHTSA); a Mercedes-Benz dealer completes any open recall at no charge.
What a history report tells you — and what it doesn’t
On a car like this, the individual car’s history is most of the decision. A history report is a record of what got reported — title brands, reported accidents and damage, odometer readings over time, and service records where they exist. That is what separates a clean, maintained example from a salvage-title or flood car wearing the same badge.
What a history report is not is a forecast, and an absence of records is not proof of a clean past — plenty happens to a car that never gets reported. That is why the honest answer is always the pair: the documented history and an in-person inspection by a mechanic you trust, on the specific car.
What would make you walk
- Oil in the harness Oil visible at the camshaft-sensor connectors or wicking into the engine wiring harness.
- Coolant in the oil Cream or mayonnaise residue under the oil cap.
- A rattle that won't clear A sustained cold-start rattle or a chain-area knock under load.
- A tired transmission Harsh, flaring, or delayed shifts, or limp mode.