Hi,
I have a 1988 740 gl turbo wagon with the b230ft engine and it has around 220,000 miles on it. My problem is that with the mass air flow sensor plugged in the idle of the car is very erratic. When I start the engine it rev's high around 1500 rpm and the drops way down starts the die out then rev's high again and it will keep doing this and sometimes it does die out. With the mass air flow sensor unplugged the car idles at a steady 800 rpm. I would drive with the sensor unplugged but the car does accelerates very poorly. So I have changed the mass air flow sensor, cleaned the throtle body, and cleaned the air idle control valve(I think thats what its called).This has had no improvement and am asking for any suggustions on how to fix this problem. Any help would be apprecitated. Thank you