Dakota stops running

[grtrat1]

1994 Dakota 2wd ext cab 3.9 auto... Truck has been running great since I built it.. I had a annoying exhaust leak and finally found out it was coming from that pipe that goes from the pass exhaust manifold to the back of the intake. It was split right by the tranny tube.. So I wiggles the pipe and it broke off the peice that bolts to the exhaust manifold. I took a short bolt and welded it to the opening of the peice that bolts to the exhaust manifold (left the pipe end alone).. Since then my truck has just quit running after about 10-15 of run time..I put it in park and it will crank right up..
Is this just a coincidence and maybe something else is wrong or do I need to replace that pipe?

Thanks
Chad