1994 Caravan 3.3, starts and dies

Since I solved my fuel problem, I decided to start a new thread to address the remaining no run condition. 1994, 3.3, 150,000, fresh plugs, wires, coil pack runs an Intrepid, crank sensor is still magnetic and cleaned, compression is 150 across the board, fuel pressure is 50 cranking and running (if you can call it running), air filter is new. Now the bad. Van cranks and fires right up, but immediately dies (within a second or 2). If you pump the accelerator it'll keep running for awhile, cycling up and down as you pump. Smells flooded and dies as soon as you let off or if you hold it to the floor or you get out of rhythm. I pulled up the rail with injectors still on it and none of them leak and all seem to be firing as they should (to the naked untrained eye) when you crank it over. There are no codes. Everything else seems to be operating normally, all fuses and relays are good. I'm hoping to try a new camshaft sensor tomorrow, and hopefully find an engine computer at the bone yard. If neither of those is the fix, I'm at a loss. The only other thing I could think of is the timing chain slipping, but I figured it'd still run, just poorly or the compression would be down. Anyone have any ideas or know how to check the timing chain w/o disassembling the entire front of the engine? Thank you very much for reading.

Update time-
Tonight I disconnected the exhaust at the head pipe (just before the cat), no change. Tried 2 different junkyard cam sensors, no change. I also picked up a PCM (engine computer) today at the yard, going to try that in the morning. If it solves my problem, I'll post back immediately, otherwise I'm going to drown my sorrows in a case of beer or 2 up north over the weekend.

Swapped in the new computer, no change. Banged on the MAP sensor, no change. next I'm going to get another map sensor and crank sensor. If those don't work, I'm out of ideas. If anyone else's got any, I'm listening. thanks

Unplugged the MAP sensor. Runs rough, but runs, SES light now on. Replaced the sensor, problem solved.