Hi everybody... everything on my 91' 740 (Regina fuel system) is new, its burnin a bit rich though, I had messed with the (dont know what its called) its a small rod with adjustable threading on both ends, one end is connected to the throttle body and the other connected to the spool....need to know if there is an adjustment that is precise or would I have to send it off to a pro to get this done, its killin my gas...

 

What you're describing is the throttle linkage.Generally, there isn't much to do with it except make sure the throttle blade is completely closed when there is no pressure on the cable and that there is instant movement of the throttle blade with the cable. Running rich means too much gas or, not enough air. So...assuming your air filter is clean and no other obstructions to the intake, there are only a few other possibilities. Regina systems use a 2.5 bar fuel pressure regulator. Using a 3 bar or higher from an LH car can affect things. Typically though, a faulty O2 sensor is at fault.

 

If you think it running rich, you can pull the plugs just to see how they look. Blackened= rich, White= lean, light coffee color= just right. I would also think that you'd see other signs of a rich burn too (black smoke, soot in the tail pipe) if it was a large loss in mileage. What is your calculated mileage? I also agree, the O2 sensor is a good place to start.

 

Sorry, been busy with my 89' 740... found out that the reason it dont start is becuz theres no juice to the Cold Start Valve....the blk/gry wire that comes from the ECU I'm asuming is a negative wire, (-) while the blu/grn is the positive wire(+)...(I'm assuming) cuz it branches off to the injectors as green wires...and the white wires being (-)...sorry about being sidetracked on this tread... my 91' is running fine and could wait,.. its not all that bad... its my 89' 740 I need to get goin...I've been using my 91' as reference... and the C.S.V on the 91' gave me 12 volts when I turn the key to 2 on the ignition...the 89' did'nt...