Hello, 

I know its an European car, however it's an overall car question. I get random rpm fluctuations at idle. It's very rare, it happens maybe once every 1-3 months. I suspect it's the throttle body and or the master air flow sensor. I have changed all of the spark plugs and coils in the summer. When i first bought the car I did clean the throttle body.

It's a 2.0L gasoline turbo charged car. F4RT Reanulat engine 225hp 165KW. 6 speed manual transmission. I have been the owner since 2019. I am the third owner of the car. The second owner is my best friend and has been the owner since 2009. The car has a little under 100K miles (156K KM) on the odometer. I only do about 6k Miles a year (10K Kilometers). I change the oil and all filters (oil, intake, cabin) at 6k miles (10k KM), or after about 11 months. The timing belt was changed when I bought it, and the V-belt + tensioner were changed recently as well. I do it myself and make sure it's done right. (timiing belt was done at a trusted mechanic)

Description of problem

The rpms world flutter around 750-900 rpm when at idle. Once it even bounced from 800-1200. In all cases, it disappeared as soon as I added a little gas. Never happens when car is at operating temperature. Only when cold, and almost always in the winter time. (only once in the summer time).

This car is my baby. It might just be old, but it still worries me when it happens.

Thank you in advance 🙂