I bought my car a month ago and it had a terrible idle control issue. The idle air control valve was making the car idle way too high, the engine basically jumped out of the hood. My mechanic disconnected the IAC and manually adjusted the idle to a perfect state. Yesterday I heard this whining noise coming from the engine and since then, the engine jumps again. I can feel it as well when it shits gears and this is on the highway. Coming to a stop, itll jump the hardest. Any ideas?