Not sure if this belongs in the technical section or not but... I put new BBK headers and h-pipe w/ cats on my '94 Mustang GT last fall before I put it away into storage. I just got it out this week and there is a fair bit of black in the exhaust and the condensation that normally comes out of the exhaust is also black. Is this just the coating inside of the pipes or something that happens with new cats?

 

normal... black is carbon, it's a byproduct of ignition... usually after a motor doesn't run for a while it blows black for a bit, go take it for a good solid run on the hiway and see if that clears it out...

the other reason for black is if it's running rich, which usually happens if it's sitting... slightly stale gas needs a little more to kick over... i wouldn't worry about it

 

Thanks. I've had the car stored before and it's been fine after bringing it out. It's always been rich, it's tuned a little rich to be on the safe side. I've never had it show up this obvious after bringing it out of storage though. That's why I was wondering if this was normal for new exhaust parts...

 

my bike blows black if i let it sit for 2 months or so, same with my stang... i don't even know if it will start now... i'm thinking the crank has rusted to the block... i haven't started it in almost a year