I have added a 3" downpipe and a 3" catback to my car. I still have the stock cat installed. I have an XEDE and uploaded the Stage 0+ map to it, but the XEDE's boost controller is disconnected.

When I push more than 12 PSI I can hear a buzzing sound. I don't think it is the soleniod for the XEDE (I thought it made a clicking sound). Is this pre-detonation? The problem occurs above 5000RPM.

What can I do now (besides not go above 5000RPM at WOT) to fix this? Would an XMAP log help somebody adjust my map until Shiv comes to DFW?

Any help would be apperciated.

 

First things first...Since the sound has come about since the addition of the exhaust, start there.

1. Check for leaks.
2. Check for clearances.

Then, if you get a clear bill of health there, pour a little race gas in. If it is knock you are hearing, the noise will more likely then not go away.

On a side note, I remember people complaining about a buzzing noise on s4s, after they installed cat backs. Since you have a three inch DP, and a 3 inch cat back, the stock cat maybe a big enough restriction to cause some funny sounds.

 

The joys of modding.

Good adive. It is possible the stock cat is making the sound....not sure. I'll throw some 104+ in tonight and get some race gas this weekend and see if that helps.