Typically six ignition coils, one for each cylinder on the gasoline E350’s 3.5-liter V6 engine. Diesel E350 BlueTEC variants do not use ignition coils for spark timing; they rely on glow plugs instead.
Understanding the engine and ignition system
The Mercedes E-Class lineup includes both gasoline and diesel versions. Gasoline E350 models generally use a six-cylinder V6 with an individual ignition coil for each cylinder (coil-on-plug). Diesel BlueTEC editions use glow plugs to heat the air for combustion rather than spark ignition, so there are no ignition coils serving as spark providers in those engines.
Coil count by drivetrain variant
The following breakdown covers common configurations found in typical E350 models across generations and markets:
- Gasoline E350 (3.5L V6): 6 ignition coils, typically one per cylinder (coil-on-plug design).
- E350 BlueTEC (3.0L diesel): no ignition coils for spark timing; six glow plugs are used instead for cold starting and combustion.
- Other E-Class variants with different engines may have different ignition coil counts; always verify for your specific model year and market.
When diagnosing ignition issues, confirm the exact engine code and model year, as coil configuration can vary with updates and regional specifications.
Maintenance considerations
Common symptoms of ignition-coil problems include misfires, rough running, and a check engine light. Replace faulty coils with OEM parts, and consider accompanying spark plugs if you’re addressing misfires. For diesel models, attention should be on glow plugs and related circuitry rather than ignition coils.
Summary
In short, gasoline Mercedes E350 models typically have six ignition coils—one for each cylinder on the 3.5L V6. Diesel E350 BlueTEC versions do not use ignition coils for spark timing; they rely on glow plugs (also typically six). Always verify the exact configuration for your vehicle’s year and market via the official service documentation or parts diagram.