Engine Idle bounces down and up when pressing the clutch in as I’m coming to a stop. It does the same thing even when I throw it in nuetral while coasting....no vaccum leaks, iac is clean, throttle body was replaced a year ago. Maf sensor is clean. Air filter new. New spark plugs, new spark plug wires. No check engine lights. It has slowly gotten worse over time and stalled out on me once recently. It doesnt matter what the temperature is outside. Any suggestions?