Volvo Repair: 89 Volvo 740 GLE immediat shutdown still persist, volvo 740 gle, air flow sensor

Question
Dear Sir,

It has been a while since I last talked to you. If you remembered, I was the one who was able to brought my volvo back up after 2 years of break down. First, I thought the problem was because the dirty connection of the fuel pump relay because I cleaned it and it started right off, at the very first time when I was able to crank it back up. Before the two year of breaking down, this symtom have happened before. The car would shut off suddenly while driving and would have problem starting it back up. I addition, out of no where, the car would have problem starting up. The engine spun. The starter worked perfectly, but the engine just wouldn't start. If I left it alone for a while and tried starting it back up again, it would work from time to time. I don't know if this is just my presumption, but it just seemed to help sometimes when I took off the air filter, left the intake port open a little to let more air in and tried starting it up. Also, sometimes I jiggled the feul pump relay a little before trying to start. That seemed to worked to. Everytime when it finally started back up, it rode as if nothing happened. So far, when driving it shows no sign of intermittency of fuel delivery. It just shuts off whenever it feels like. While running, if it shut off, it would not shut down completely until it completely stopped. The engine would run slower and slower until it is off. while shutting off I could not accelerate or do anything but to let it turn off.

Here are additional information that I think it may help.
1. I ounce messed around with the air flow sensor located at the air filter box by turning the screw back and forth so much that I did not know what the original setting was.   
2. I still have not changed the fuel pump relay. I chek the inside circuit of the relay. There was no loose solder.
3. The fuel pump is still the very first one that came with this almost twenty year old car.

I realize that this is very hard to pin point the problem just by reading my post. I just hope that you could suggest the possible problems, so that I could eliminate it one by one until I eventually find it. Always appreciate your help, sir.

Note:
Vihicle make: 89' Volvo 740GLE automatic jetronic system.  

Art  

Answer
sounds like a fuel pressure problem.it could very well be the main fuel pump shutting down.it would really need to be driven with a fuel guage on it to check pressures when driving and see what they are when it shuts down.it could also be a problem with the in tank pump not supplying fuel to the main pump well enough.I would remove intank pump and check its operation and its hose.