Golf 3 TDI: Cold Start Problems & Solutions

Hello everyone. Maybe someone here can help me. I'm completely desperate.

My Golf 3 Syncro TDI 90 hp, manufactured in 1996, won't start when it's cold. I've already replaced the glow plugs, and there's power getting to them. I've also replaced the four-pin temperature sensor in the cooling system. I've checked the timing, and everything seems to be okay. If I disconnect the temperature sensor, I have to pre-glow for a long time, but then it starts, although it runs very rough. After a while of struggling and shaking, everything suddenly goes back to normal. If it's been running for a moment, it starts without any problems. It also pulls cleanly. With the engine running, if I plug the four-pin temperature sensor connector back in, the display is correct, and the engine runs normally.

The sensor is now showing a blue light, which was previously yellow. This indicates that it is the correct setting.

I'm just not sure what to do anymore. Oh yeah, I also replaced the oil cooler lines.



You're welcome in advance, Benny.

Hi,

Does it not suck up air/foam?
Please periodically check the injection timing using the TDI timing checker. If the timing changes, search for "crankshaft screw 1Z" in this forum.

Best regards, Rainer.