I have a 2000 Impala with about 115k. I just replaced the upper intake manifold because it exploded when I tried to start the car. No engine damage or coolant in the block. I replaced the manifold, gaskets, and valves that came with the kit. It started right up. I let it run for a while and after about 15 min or so it will rev way up, crash way down, rev up again, down and dies. I then hear a "whooshing" sound. Started again and (in park) gassed it to about 3k rpm and it will sound fine and just die without. It fires up immediately again every time. I read on this site about a similar problem and looked like it could be the MAP sensor. Could it be that since I used a new manifold, the sensor won't work right? I am afraid to drive it and need my car to work. Can anyone please help???