In Reply to: Surge Problems w/1991 BMW 525i multi valve posted by Mark on January 27, 2000 at 02:03:06:
The early M50 engine had coil problems. I had similar problem with my 91 at 100Kmiles. I changed the coils and it got better. If you don't what to spend the bucks you could by two and change them around until you get the bad ones out. But it is just a matter of time before the others go out. I had some flat spots during hard acceleration and changed the 02 senser to fix that problem. Good luck!