X5 3.0 possible safe mode problems

[Cgswss]

Thursday (1 week ago) I was driving one way about 75 mph. Engine started missing, ended up would not rev about 2000 rpm. Restarts fine but really won’t rev much above idle. Towed to “all car” service station. They can’t decide what’s wrong with it. They want to replace the fuel pump, I think it is in some sort of “safe” mode. They aren’t getting any error codes on their scanner

I have heard that only some scanners with bmw specific software can find some special bmw codes

It’s an 2006 X5 with abt 135,000 miles. 3.0 engine. I have been driving it with a leak in the cam cover gasket (waiting for a service window). As it happens today was my appointment.

Any suggestions?