smoke possibilities?

[vex]

After driving home I'm wondering if some fluid isn't accumulated in my exhaust. For whatever reason Smoke does not increase out one pipe or the other when I cover the other up. Instead it appears to just build up in the single chamber until I uncover it at which point both chambers increase output of smoke. Rather pecuiliar.

Beyond that I have a few things I may try to remedy the problem... I just have to wait for the engine to cool down a little.