I know there has been a few threads started with owners asking this exact question, but I haven't seen any solutions or follow-up. After receiving the C161E cel in late May, I had my AYC pump replaced just a few days ago. $2,000 dolllars later I got my car back yesterday and I am getting this "groaning" noise right where the AYC pump is located. (passenger side rear-end) The noise is intermitant, however the noise is exactly what is heard in the videos below;

http://www.evoxforums.com/forums/showthread.php?t=57995





Like many Evo X owners, I HATE bringing my car to a stealership more than I have to. They can rarely replicate a noise, and they are never able to fix a problem the first time around. I've searched extensively, but I may have missed the answer. Can someone please point me in the right direction to a thread that might have had/have the solution to this noise? I work in the medical field, so it's very difficult for me to continously drop my car off at a dealership. Obi-Wan I need your help!!!

 

never seen such a problem, but it could have a couple of reasons..

first, I'd make sure you have oil in the diff.. both oils in the rear diff to be specific..

second, it might help to bleed the ayc/acd system once again, you might have some air in the system..

 

Thank you for the reply. I was thinking the dealership needed to bleed the pump system again as well. The "groan" or buzz could be the solenoid activating and only drawing air. The diff oil is full in the trunk, however I will have the dealership check the other.