It dies when i slow down to approach an intersection or a stop sign. It doesnt idel the same since the intake manifold was replaced. The electronic idel pully is in place and there isnt any leaks in the vaccume hoses, also, there is no gas leak. It never did this before some family members replaced the intake-manifold.It does great on the highway but not around town...97 Grand Prix, 3.8 .... Please help!!