Developed a problem on my ST g35 revup on a 12 hour drive in the last hour the car threw a P1072 System too rich bank 1 code, it drove ok just with an erratic rougher than normal idle going rich lean rich lean on the wideband. I didnt boost it too hard but i could tell there was a power loss.

I cleaned the maf and thought id replace both AFR sensors (NTK) and cleared the code. Car is running the same as when the code was thrown, under boost im running 10:2ish AFR with very noticeable power loss and also the BOV sounds very weak and airy sounding and doesnt flutter at low boost like it used too. It sounds a lot weaker than when the car was running strong.

Does this sound like a boost leak? I did a cigar boost leak test and noticed that I got smoke out of the boost gage filter (cracked) I replaced that and also I am getting a small amount of smoke out of the bov itself.

Or do i really need to pressurize and soap the system and look for a massive leak.

Thanks!