Octavia: Cold Start Problems, No Glow Plug?

Hello,

My Octavia 1.9 TDI, manufactured in November 1997, with 130,000 km, starts very poorly in the mornings when it's cold. Warm starts work fine. This wasn't a problem last winter!

The preheating indicator light on the display comes on normally, but I don't think it's actually preheating. I measured the control voltage at relay 103 (which is the correct one, right?). There's no control voltage at the relay when you select preheating; it only reaches 12V after the start sequence. This doesn't seem normal, does it?

Does anyone have any ideas?

Greetings.
Walter.

Hello,

- Check each glow plug individually for functionality (using a light bulb in series or an appropriate ammeter).
- Check the power supply to the candles; inspect the fuse strip (also for corrosion).

If the glow plug system is working correctly, check the coolant temperature sensor for plausibility. For a test cold start, disconnect the sensor connector. If that works, replace the sensor.

Best, Andy.

...if you don't have an ammeter handy, a regular 55W car bulb can also be used. Connect the positive terminal of the battery to the bulb and then hold the bulb against the glow plug. If it lights up, it's okay. If it only glows dimly or nothing happens, you need to replace the glow plug, but be careful when removing it. If the engine is over 6 years old, you need to be very careful not to damage the threads!