I'm thinking big vacuum leak or MAYBE unstable fuel pressure. My Ranger was doing this and it turned out to be fuel pressure, the pump was not running right due to corrosion on the circuit board that held the fuel pump relay. (The little transistor circuit that pulls the relay in was intermittent due to the resistive path thru the corrosion. The Crossfire is not the ONLY vehicle that leaks water down on the passenger side - and electronics get wet!)

THIS kit will tell you what the fuel pressure is (works really well for me cause it has two sizes of Schrader valves, the Ford Ranger size and the Crossfire size). Makes checking fuel pressure almost as easy as checking tire pressure.

https://www.summitracing.com/parts/otc-5630