RF,

The 740 turbos use a low impedence injector and as I recall 2.8 ohms is correct. It sounds like you have (a) injector seal(s) leak(s). Not hard or expensive to fix. There are seal kits for a few bucks and it requires pulling the fuel rail and replacing the o ring seals. It could be the bolts holding the fuel rail in place may be loose and that could result in the injectors seals not be seated. Pushing the rail down into place and tightening the bolts may resolve the problem. Check the archieves and 700/900 FAQ for more details. Injector seal leaks can cause a lean condition that will produce a rough idle. and miss fires. Spray a little throttle body cleaner around the base of the injectors as the car is idling ... if the seals are leaking the carb/TB cleaner will cause the engine speed to increase or the engine to stumble briefly. A properly running 740 230FT engine is significantly more powerful than the N/A B230F in the 240. Hope this helps.