Hello,

 

I got an annoying random engine shake at idle with no change in rpm. I could drive for 1 hour in the city and not have a single shake, then in 20 minutes it could shake 2 times. All this happens at idle, the engine runs smooth, then for 1-2 seconds the engine shakes then goes back to normal. The local Skoda shop found nothing on the tester. What could it be?

 

2.0 TDI , engine CFFB.

 

Thank you.

Do you mean rews will drop to ~700rpm for a moment and then ECU will try to compensate and rew to ~1000rpm and then back to ~800rpm ?

 

I had this problem when I've set my tuning box to most fuel efficient mode

The RPM gauge shows no change, keeps pointing at 800 rpm and doesnt move. This only happens when the instant consumption shows 0.4l/h. When the engine is cold and it idles higher at 1000rpm this doesnt happen.