Safety Warning
DIY auto repair can cause serious injury, fire, or vehicle damage. These guides are for informational purposes only. Always follow OEM torque specs, wear PPE, and consult a certified mechanic if you are unsure. You are solely responsible for your safety.
CDI overrun mode, function - GF07.16-P-3008P
ENGINES 642 in MODEL 219.3, 209.3, 211.0/2, 209.4, 211.6
ENGINES 642 in MODEL 461.3
ENGINES 642.9 in MODEL 463.3
ENGINES 642 in MODEL 221.0, 203.0, 164.1, 203.2, 251.0/1, 164.8, 221.1 up to model year 2008/YoM 07
In overrun mode at an engine speed > 1600 RPM and without depression of the accelerator pedal, actuation of the fuel injectors (Y76) is interrupted (zero delivery). To do this, the CDI control unit (N3/9) reads in the following information:
- Accelerator pedal sensor (B37), accelerator pedal position
- Crankshaft Hall sensor (B70), engine speed
In the overrun, the CDI control unit interrupts the actuation of the fuel injectors and lowers the fuel pressure in the rail via the quantity control valve (Y94) and the pressure control valve (Y74).
If the accelerator pedal is depressed again or the engine speed falls below 1600 RPM, then the so CDI control unit re-actuates the fuel injectors and increases the fuel pressure in the rail via the quantity control valve and the pressure regulator valve.
| Component description for crankshaft Hall sensor | B70 | GF07.04-P-6220P |
| Coolant temperature sensor, component description | B11/4 | GF07.04-P-6040P |
| Component description for quantity control valve | Y94 | GF07.05-P-6010P |
| Component description for CDI control unit | Model 203, 209 N3/9 |
GF07.16-P-6000P |
| Model 211, 219 N3/9 |
GF07.16-P-6000T | |
| Model 164, 463 N3/9 |
GF07.16-P-6000GZ | |
| Model 221 N3/9 |
GF07.16-P-6000SX | |
| Model 251 N3/9 |
GF07.16-P-6000RT | |
| Model 461 N3/9 |
GF07.16-P-6000GX | |
| Accelerator pedal sensor, component description | Model 203, 209, 211, 219 B37 |
GF30.20-P-2010P |
| Model 164, 463 B37 |
GF30.20-P-2010GZ | |
| Model 221 B37 |
GF30.20-P-2010SX | |
| Model 251 B37 |
GF30.20-P-2010RT |
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When to See a Mechanic
Stop DIY work and contact a certified mechanic immediately if any of the following apply:
- • You smell fuel, burning insulation, or see smoke.
- • Brakes feel soft, pull hard to one side, or make grinding noises.
- • The engine overheats, stalls repeatedly, or misfires under load.
- • You are missing required tools, torque specs, or safe lifting equipment.
- • You are not confident in the next step or safety outcome.