My son has been complaining that his 96 850 w/318K has been stalling. Mostly at intersections and slow speed driving. He also has stated that is will loose power when driving (yesterday on the interstate).

We've replaced the fuel pump relay. I have a fuel pressure regulator and new fuel pump on hand. I talked to the previous owner (15k->300k) and he told me that he had twice replaced the fuel pump, and perhaps a mechanic did something with the flame trap (like remove or disconnect it).

I also noticed that there is some positive crankcase pressure (vapors rising from the engine if I remove the oil fill cap at idle).

I'd like some advice on weather I should just install the regulator and pump or if I should do some more diags first.

If or when I change the fuel regulator, is there any special tools or tricks I should know about?

Thanks for any help.

Chris