Couple months ago my 99 E39 (528i) would not start. My friend/mechanic comcluded the problem to be either the fuel pump or the fuel pressure regulator. Being these components are oringal and nearly 16 years old, I decided to replace both, plus a new fuel filter.
After the new fuel pump, fuel pressure regualator and fuel filter were replaced it takes an extremely long time to start the engine when you turn the key. It cranks for maybe 7 seconds or more. It always starts, and once it starts runs and idles fine.
Once in a while it will start up like it should, but most of the time takes way too long.
Any suggestions?