The 525i is a fairly gutless car as far as acceleration. That said, mine has certainly seen some crazy top end.....
Basically, you're looking at what ammounts to a tune up, pull the plugs, replace them, make sure that your valve cover isn't leaking into the plugs (you'll notice oil/around your plugs, and a valve tap from hell) make sure your airbox is clear, and that your exhaust isn't swiss cheese. After having a hole in my exhaust for a month, then replacing it, I'll tell you that an exhaust leak in that underpowered of a car turns it into a dog.
Although they're the automotive equivalent of a lazy fat chick, the e34 525i is still a nice car. It won't accelerate worth a damn, but still, I love em.
If you want to read codes, on the later model cars, go get a codereader, 125 bucks that gets rid of the guesswork in most of the stupid shit you'll encounter. Other than that, your airbox and air intake should be checked. I had a similar problem on my 6er, and replacing all the air intake hosing for 50 bucks, basically turned her back into sportscar. If the air intake hoses looks too old to be on your car, replace it, at least, thats the rule I go by.
Last edited by d3ity; 05-30-2006 at 02:00 AM.