Soot around Exhaust tip

[Alban61]

Had a problem with bucking, hesitating, and change in exhaust tone. Dealership did diagnostics and found bad plugs and wires. They cleaned the injectors too. Problem with bucking etc. is solved, but still having that change in exhaust tone. Noticed black soot at the tip of the exhaust. Cleaned that out but it formed back again within a couple days. Exhaust sounds deeper, and seems to drone alot more than usual. Noticed a decrease in power too. Dealership told me that there was no exhaust leak. Any suggestions? Also hear a rattle at higher RPMs, but I think that's just the covering on the catalytic converters. Will take care of that with some metal straps.

 

[huskyfan23]

It's probably a carbon buildup, dunno of a fix though.

 

[Alec]

Maybe you're getting too much fuel: that is likely a Fuel Pressure Regulator problem.

 

[Alban61]

Thanks guys. Will check about the FPR. Would that also cause the exhaust tone to change?