My Volvo is not behaving itself

'85 Volvo 740GLE, 2.3L, mileage 262,832 has been having HUGE issues. We got it used, and has always taken a 4-6 seconds to start. It would also lose power at highway speed up a prolonged hill. If I pulled over, turned the engine off, waited a couple of minutes then started it again, it would operate normal. This latest development started while driving in stop and go traffic (the temp has never registered hot). It bucked a couple of times (as if I was just learning how do drive a stick), the tackometer went up and down a couple of times, then it stalled out. At first I thought that the fuel guage was lying to me and I was actually out of gas. My husband brought some gas, put it in and shook the car. It started up and we drove to a gas station to fill it. The car now had a full tank. It ran ok until it got down to 3/4 of a tank, then the same problem. I had parked on a slight incline, so I pushed it back to level ground, shook the thing and cranked it. It started but wanted to stall. I got to another gas station close by and filled it. I drove to my next destination, parked on an opposite incline and when I needed to start it again, it wouldn't (this is on a full tank of gas now). It finally started (foot to the floor and a 10 second crank), wanted to stall out 2 minutes down the road, I revved it and it maintained itself. The tack jumped 2 minutes later going up-hill, then it stalled out. Turned over after shaking it and putting foot to floor again. I made it to my kids school, turned it off and waited for hubby. He came and found a hose loose and pushed in the flame trap nipple which had worked itself loose, but not completely out. He replaced the trap in the nipple which was completely clogged and glued the hose back into place that weekend. It worked fine for 3 days, then the tackometer jumped again and it stalled going down hill. Shook the car, it started (each time it has taken longer to restart). I got it home and the next morning it would not start at all. We have checked the relay, heard the in-tank fuel pump running, checked the injectors, changed the fuel pressure regulator, changed the spark plugs, changed the coil and changed the ECU. When the engine cranks, fuel dumps out of the FPR, so we've gone away from the fuel pumps. It ran yesterday 2 separate times for nearly 2 hours with no problems. I tested its restart 5 times and it started up just fine. But this morning will not start, at all. It tried to turn over but never made it. Any ideas? Because I am loosing my mind.

As I've put so much into this car, I cannot afford much, but if this service can help, a small donation is worth my going without a cup of coffee today. Thanks.