I wrote in a few months ago with this problem and I still haven't got it right. '84 244 2.3 I've got new throttle switch,fuel regulator,air flow sensor,temp sensors,checked fuel pressure,checked O2 sensor,removed what was left of catalytic convertor,(2 years ago the inside melted away and came out tailpipe)changed coil,cap,rotor,plugs and wires. Nothing has made any change. It runs very rich and "hunts" at idle.(RPM up and down) Fuel milage is down to about 12 MPG with a cloud of black smoke following me around.Do I need to replace the engine control module or what. And since I'm sort of new to wrenching on Bricks, is the engine computer the one under the hood or one of the ones inside? What's a decent price for a junkyard control module? My Dads Volvo mechanic has a good collection of wrecked cars but he also wanted $3,000 to install a used tranny and radiator on a '86 740. I've got to be prepared for this guy. Thanks.