Hi all, I have a 90' 740 B230F in Australia.

Problem 1 - Cold start problems. It starts on a cold morning but runs extremely rough, like its only running on 2 - 3 cylinders, and if you depress the accelerator it will stall and will not restart until you dry the spark plugs. If you let in run rough for a minute or 2, the car runs ok and smoothens out.

Problem 2 - Blows black smoke, when accelerating hard, and you can faintly see it when idling, poor fuel consumption, unresponsive when you touch the accelerator. All this above applies to problem 1.


Now I also have a 93' 940 B230F in perfect working order, and I swapped, plugs, ht leads, o2 sensor, amm, coolant temp sensor, fpr and this made no difference whatsoever.

So I put the ecu from the 9 into the 7 as they are both Bosch 935 units and now the cold start problem has gone away, idles perfectly but still black smoke, and a fuelly smell from the 740.

What is wrong with the Ecu, and why am I still blowing black smoke.



Any ideas?