What would a cracked down pipe do

[574-240sx]

My car has been back firing every once in a great while. then it seemed to happen more often. Then it started to happen anytime I would get on the throttle pretty good. Then as soon as I back off it pops/back fires out the exhaust a little. Then the other day I have noticed a exhaust leak. I took a look then discovered at the top of my down pipe below the weld on the flange a 2 inch long cracked. This was a home made down pipe, I guess it was bound to happen. Would this cause a backfire? This only seems to leak under boost. I will replace it this winter. I guess the car will go gown early this year.

[Structure240sx]

once on an hour long trip my downpipe rattled loose. some of the bolts fell out and the rest hardly staying in. once i got to my destination it sounded aweful like you are describing.

also think about it. whne u upgrade from stock exhuast to an aftermarket 3" or so you can hear alot more little backfires that the stock muffled.

[574-240sx]

I have always had the exhaust it started just a a few weeks before the i noticed the crack on the down pipe and it has gotten worse. I drove it around tonight and it seems to have a mis. I will pull plugs in the morning I think one of them may have fowled out.

[Structure240sx]

i was using the exhaust as an example. with a crack exhuast will be passing through, sorta like a MORE open exhuast.

so comparing the noises your hear from going to aftermarket exhuast from stock

then comparing any noises you might be hearing now with a crack in the exhuast, especailly that close to the turbo

[574-240sx]

Thanks Structure240sx for your help. I guess I'm going to put the 240 up for the winter before the rust monsters get it. I will have to fab a new down pipe, well at least the first 12 inches from the flange.