BMW TDS 325 preheating system

BMW TDS 325 preheating system:

I'm using rapeseed oil as fuel. The problem is that when starting the engine from cold, the starter motor has to crank for 4-5 seconds before the engine starts. When starting the engine after it's been warmed up, it starts immediately after the preheating period and runs smoothly.

On older VW models, it was possible to remove the connector from the water temperature sensor, which would cause the engine to glow every time, regardless of the temperature. With just 5 seconds of pre-glow, it would start immediately; the same applied for cold starts.

I'm not sure if it's that easy with a BMW. Or whether the ESP would be controlled correctly in that case. Apparently, there will likely be an error message.


Therefore, the question is: Is it simply a matter of unplugging the water temperature sensor?

The glow plugs are new, and the engine starts immediately every time with diesel fuel.

They have an EDC-ESP system, with a temperature sensor already installed, etc., plus a mass airflow sensor. You can probably guess the rest. Just out of curiosity: How long should the engine be able to run on oil alone? Best regards.

Okay, I'll run a cable to install a button that will interrupt the circuit. That should also cause the ESP module to power down early.

With the current fuel level, he should be able to drive a few more kilometers; I don't have any concerns based on my experience! I'll let you know when he runs out of gas!

I already have my concerns. I've had quite a bit of experience with VW diesel engines, having driven them for well over 100,000 km.

Since your fuel injection pump is map-controlled, the injection timing doesn't match the cetane number being used. Only a reprogramming would fix this. However, the fuel must be preheated, otherwise the cetane number will result in poor atomization in the swirl chamber, leading to incomplete combustion and leaving residue.

With the engine used back then (likely an ESP system), I experienced fewer problems with carbon buildup in the combustion chamber due to the good tuning of the pump, but I had issues with the polymerization of the plastic components. This resulted in a timing belt failure caused by a defect in the vane cell pump within the ESP system. Due to the inevitable increased fuel consumption and the overall absurdity of it all, I no longer use gasoline.
Best regards,