x5 in limp mode - I think???

[mrothwell]

I was running down the freeway at 77mph, fairly flat, when all of the sudden I start loosing power. Originally it felt like the transmission shifted down, but I then realized it was the engine loosing power. I stopped, and the engine idles fine and even when I hit the gas, it revs to about 2000rpm then backs off. If I put it in gear, it goes, and I can manually shift thru all 5 gears. I feel a distinct shift, so I dont think it's my tranny. I tried to limp it home, and it just got worse, originally it would run to almost 2k rpm, but then got to where it would idle only. I have a service engine soon light, but no other indicator. If I shut it off and then start it up, it runs better for a few seconds, then bad again. It's got to be a sensor or possibly a fuel pump (just a gut feel).

Anyone got any ideas????

2001 X-5 4.4 sport.

Thanks.