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.
DME Control System: Description
The 911 Carrera, 924S and 944 models are equipped with the Bosch Digital Motor Electronic (DME) engine control system. The DME system uses various data sensors to monitor intake air volume, engine speed, crankshaft position, coolant temperature, intake air temperature, and throttle position. Signals from these sensors, as well as a start signal and oxygen sensor signal, are sent to the control unit.
The Control Unit (CU) is a microcomputer. Using information obtained from data sensors, the CU determines the correct amount of fuel and optimum ignition timing.
The 924S and 944 DME control unit switches from open loop to closed loop operation when the coolant temperature is above 113°F (45°C), and when the oxygen sensor temperature is above 480°F (250°C).
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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.