poor idle

Volvo 850 (very) high idle at startup, then up and down

Idle Air Control Causes Poor Idle It appears we have a winner. Took out the IAC, sprayed it liberally with carb cleaner (didn’t touch the connector, don’t trust carb cleaner around those, but I might be paranoid) and replaced. Also cleaned the flame trap a bit (wasn’t too bad, actually, same with the throttle body). […]