I own an orange 2007 RS.1. I have a Sharkwerks rear exhaust bypass, otherwise box stock. 15,400 miles. Plugs never replaced, air filter brand new (old filter fine). Street driven only. Perfect overrev history. I am observing one side (drivers) white and dry in color, the other sooty dark. My dealers "reader" is broken, awaiting replacement unit from Germany. Tech says "fuel trim" related. Questions: Are there adjustments for each side independent of the other side for fuel trim (mixture?)? Any other ideas what could be causing this? Thanks in advance for your learned and insightful advise.

 

Bueller....Bueller....

 

Looks like i'm the only one that cares about your fuel trim issues...

let me know what you find out with teh OBDII reader...

 

Oh and for the record, we have the exact same car, Orange/Black 2007 GT3RS...

 

I care but have no answer and am awaiting the verdict.

 

Thanks Jamie_GT3. As soon as the dealer gets his reader in from Germany, and I get the car in, I will give an update as to what caused the different exhaust colors.

 

Great color Jamie!!

 

Mine did the exact same thing when I had the SW bypass on. One pipe (passenger side/drivers side US) was always a lighter shade.

Now I have the full M&M race exhaust with no valves on, both pipes are the same nice shade of grey

 

Have you checked to make sure that both valves are opening and/or connected properly?

 

RAudi Driver, yes I checked that they were both still properly connected - not sure about if both operating properly. Any way to easily check this out? Can I have someone cycle the Sport button, and/or rev the engine while I observe? Will the valves operate w/o load and merely revs? Thanks for the info?

 

i believe the valves are purely vacuum actuated, so I think revs will activate them, not great for the engine to no load rev, but to troubleshoot something...

 

Mine does the same thing. I have no idea why. BTW, I also have a Sharkwerks bypass.

 

Thanks JC2GT3, you are the second other person with a SW bypass to report this - including me, that's three. I guess they don't flow evenly.

 

I think it has more to do with the valves than the bypass. After so many years my exhaust valves were rattling even in sport mode, so I suspect that the exhaust gases were causing them to close slightly which would possibly cause the uneven flow.

That's why I went for a full valveless exhaust

 

Are you referring to the vacuum activated valve that opens in sport mode? If so, I unplugged the connector to cause it to be open all the time (what can I say? I love the noise!). I am not sure how/if that would effect the variation in the tips.