Go up and down revolutions, jetta a2 rattle "91

Hello good afternoon/days/nights!
I have a problem with my car, which is an A2 mod. 91 export fuel injection. I'm going to the point. The car has had a problem and they have not been able to detect the mechanics where e took them. The car takes time to turn on some times. Since the revolutions are on and fall. Until yesterday that practically it stopped twice, in the second it cost me to turn it on, up and down the revolutions and also dull. Also and noted a burnt oil smell inside the chest, the engine is stained with oil, it does not spend too much oil, I don't know it. The consumption of gasoline is normal, approximately 9 lts/km and the last service was done about 5 months ago, Nadamas did not change the gas filter, I will do that today in the afternoon. Well I hope I have narrated what you need to help me, I wait for your answers. And thanks in advance. For the next one took a photo of the engine.

Friend you have to make a cleansing, your iac valve as well as the admission body and tests as it goes after cleaning the battery a minute connects and give it contact it and you give it again you have this three times and then you give Arranke, and you take a tour to see how it goes