Have recently bought my latest Octavia 3 but still don't understand why I continue to experience, at certain times, high engine idle speed. 

Petrol or diesel? Manual or DSG?

 

If diesel, it could be a DPF regen, check this out:

 

1.5TSI?

53 minutes ago, pist0nbr0ke said:

Petrol or diesel? Manual or DSG?

 

52 minutes ago, PetrolDave said:

1.5TSI?

 

Hold on, I'll get my crystal balls out again! 

 

 

Maybe

The idle speed of the engine is changed for a number of conditions:

  - When the engine is cold -> the idle speed is increased based on the coolant temperature

  - If the engine is very hot -> the idle speed is increased to improve coolant flow

  - If air conditioning is active -> the idle speed is increase 200rpm to improve the efficiency of the compressor

  - if the battery is low & needs charging

  - if the clutch pedal is not 100% depressed the revs increase to assist with pull-away (linked to the 1.5 tsi issue above)

  - if the vehicle is moving (clutch pressed) the idle speed is increased assist with the next gear/clutch engagement

  - if the vehicle is moving & the clutch is engaged the idle speed is increased to around 1000rpm (known as "idle drive" to prevent the engine from stalling)

  - if the regeneration is active (on a diesel) the idle speed is increased to 1000rpm

 

There are probably many more but basically it is normal the the ECU modulates the idle speed as it needs or as an assistance feature to aid pull-away/clutch engagement.

This is not special for Skoda, all manufacturers will have similar software for controlling the idle speed.