Hi everyone, I've just bought Peugeot 306 XR 1.6i '97 and I noticed a problem. When engine is warm it doesn't work smoothly during idle work. Time to time revolutions fall down a little (from 800 to about 700) and oil pressure bulb turns on for a half of a second. Then revolutions get up. The situation repeats time to time. Oil checked. Service says that they checked computer and it's ok. What's wrong? How make it good cheaply? Greetings Michal