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).
It now idles normally! Haven’t taken it out for a test drive yet (transferred the insurance to my 740 wagon, so need to get some temp plates) but just happy that it now idles fine. Productive day overall, fixed the seat heaters and power mirrors (err.. it was the fuse. When I bought the car a little over a year ago, the previous owner said the switches were broken, I believed him.. Live and learn) fixed a few cosmetic bits.. And got it to idle nicely again.