Hi everyone.I need an expert advice. My Honda City Vario 2005 has just developed some issue of RPM surging up and then going back to normal when AC is turned on. In general before this issue when AC was turned on, the RPM used to move slightly up (from 700 idling to 800) and then goes back to normal (700). But for last two days, when AC is turned On (or restarts after tripping) sometimes the RPM goes up to 1500 or 2000, then there is a click sound of compressor turning on and then it goes back to normal. My idea is that the compressor doesn't turn on right away and since the ECU is programmed to raise RPM, it increases the RPM which goes to 1500 since there is no load of compressor. As soon as the compressor is turned on, RPM gets back to normal again. What can be the possible issue? It doesn't happen all the time therefore I am unable to get it checked. I took it to workshop but issue vanished at that time but appeared again later on. What should I check? AC wiring or sensors that increases RPM?