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I would check the fuel pressure regulator. First make sure there is vacuum in the hose running to the FPR... sometimes the intake manifold port clogs with crud and needs to be poked out with a small drillbit or nail. If there is vacuum to the FPR, sniff the vacuum port on the FPR and make sure you don't smell gas. If you do, then the FPR should be replaced because it is allowing raw fuel to be sucked into the intake manifold. Finally, you should test the function of the FPR. You can either do this by checking fuel rail pressures with a gauge (professional method) or by disconnecting the return line at the FPR and checking to make sure fuel is returning to the tank (ghetto method). I usually do this by attaching a long rubber hose to the return side of the FPR and run it into a large glass jar and watch the fuel come out. At idle, fuel should be literally pouring out. Of course, be careful and use common sense when working with raw fuel near the engine.

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Matt L. -- Cary, NC -- '89 740 sedan -- '91 740 wagon