Documentary: LD errors on the Sprinter 315CDI, two-stage charging (Solution)

Hello,

In this specific case, it was a Sprinter 315CDI with a 2.2-liter engine, Euro 4 emissions standard, and a two-stage turbocharging system using an exhaust-side switching valve on the small turbocharger and a vacuum-controlled wastegate on the larger turbocharger.

The following documentation applies to all vehicles with two-stage charging via valve control (not VTG).

Error description:
Vehicle in emergency mode, maximum speed of 100 km/h on flat roads, engine check light is illuminated, DPF clogged, maximum achievable boost pressure (via VCDS, EOBD - emission-related parameters) approximately 0.5 bar relative.

DPF removed and cleaned.
Maximum achievable boost pressure at low RPM (1400 rpm) is now 1.1 bar (relative), while at higher RPM (2500 rpm) it is 0.8 bar.
Wastegate connected directly to vacuum source -> resulting in 1.3 bar of boost at higher RPMs and with a light throttle input.

The two solenoid valves for the vacuum control were replaced (approximately €100), and it's working again .