I purchased a 2001 X5 with the 4.4l engine. The previous owner had the car die and him and was starting to remove the engine and gave up on it. I bought it along with a running engine with 115k miles on it from a reputable wrecking yard. Of course I did all of this without knowing that this is one of the "worst" (according to some) BMW engines.
My question is what do I check on the replacement engine before installing? Timing change guides? Water Pump? Seals? Vacuum Lines? Hoses?