I have a few exhaust leaks I want to fix. All of the leaks are on the down pipe between the headers and the cat. I replaced the gaskets at the header end and they are already leaking after a few days of driving. Also there are a lot of cracks in the downpipe/ front pipe, some were attempted to be fixed by the last owner by welding on top of the cracks. they just welded on the surface w/ out much penetration. Should I pull the pipe off and try to fix their welds and the new cracks, just replace the pipe or save up and do a full new exhaust?