erractic rev. PLEASE HELP URGENTLY on 1999 BMW 328i

hi, i have a 328i e46. while driving the rev falls and then picks up and falls again esp when i leave the accelerator and then press it again. At the sam time there is a noise from the back of the car. no one can tell me what the problem is not even the agents. Please help

by in Alamance, NC on May 13, 2009
2 answers
ANSWER by , May 13, 2009
This needs to be looked at by a competent shop, one who will diagnose the problem. It's impossible to do that without seeing the vehicle. Can you take it somewhere else? Is there a BMW Dealership near you?
ANSWER by , April 18, 2010
you might want to check the idle control valve