SLOW VW GOL VARIATION

Hello friends, I have a problem with a Volkswagen Gol 1000, when I turn on it works in idle for 5 sec, then the march begins to vary. up and lowering the engine acceleration by itself. I would like to help me. Its injection system is Bosch MP9. I need to save what are the elements to verify. Of course. Thank you!

Look at the mangitos that goes in the air filter, it is possible that a regulatory valve that does not work and also look at the tubes that go near the quadolimetro