When starting from cold, the idle is very uneven for the first 20 seconds. The engine even wants to die. If you increase the revs a little, the cylinders work quite evenly. After the first 20 seconds, the problem disappears and the engine runs well. I tried a different MAF sensor but it didn't change anything.

How cold is the ambient when trying to start?

 

What engine do you have?

Edited 27 October, 20241 yr by SuperbTWM

Have you looked on line for likely causes?

I would suspect a blocked DPF or a broken injector nose.

If you have an OBD2 reader for your diagnostic port, there is a good app for reading the DPF ash content.

The above post by me was in the wrong place and shpuld be deleted.

5 hours ago, SuperbTWM said:

How cold is the ambient when trying to start?

The engine is 1.8 TSI, 118 kw, gasoline. The outside temperature does not play a role, but the peculiar thing is that in warm, windless weather, the start is fine. If it is windy, the cold start does not work smoothly. If the start is normal, the engine revolutions are 1200 rpm /m. If for the first 20 seconds the engine idles, then the tachometer shows 1000 rpm. In winter, a cold start is never proper. A warm or lukewarm engine starts normally.

Have you got a diagnostic tool?

3 hours ago, pikpilot said:

I don't have a diagnostic device myself, but it has been looked at in the repair shop and there are no errors in the memory. The candles, ignition coil have been checked. Everything is fine with them. I have looked in the cylinders with a camera, the injectors are not dripping. I tested the MAF sensor myself, but it did not change anything. I am wondering if the temperature sensor and the oxygen sensor is fine. They have not been replaced. The mileage of the car is 200,000.

 

Try unplugging the coolant temp sensor and see if it starts any better.