as above the Co mat be far too High, need analyser to check, but as stated Half a turn with a long "alan key" anti-clock, once it running and gets Hot you can play with the Co adjuster...again anti-clock...very small movements of adjustment you should hear the engine respond to a weaker mixture run faster / smother....at least then able to get it set a garage to check / adjust 1.3 to 2.0 ideal, the other item to give over fueling, leaking 5th injector, easy check remove with pipe still on, bridge 30 / 87 pump runs all time, now with 85/90 psi at that injector, so check on leaking , rare for these ever to give problem back in day...but must check, also worth checking the pressure actuator , thats the 2 pin plug on the front of the metering unit, use meter on Ohms, you should see 16 to 21 0hms across the pins...if no reading, it means 12v in the past has been applied to it for a period and burnt out the "Bi-metal element" and the pressure cannot return to normal running, seen it back in the day..but rare..you see this unit adjusts the fuel pressure for starting Cold only..rather a delicate unit...seeing only voltages of 2v to 9v tops and that at a pre-determind time of seconds only, cooling itself re - the Bi-metal princible.. just to let you know, hope yours ok. Peter.