Volvo Repair: 1992 Volvo not getting gas, pump cylinders, volvo 740

Question
1992 Volvo 740 Wagon NON turbo. The car has been sitting for over a year. I have cleaned injectors and throttle body, replaced oil, plugs, fuel filter, fuel pump. Cylinders have 150 PSI each. Motor runs well, although at times it will just fade out while the gas pedal is depressed. Because it sat so long, I immediately figured the gas was dirty. I put Seafoam and Octane Boost in it. Then it ran fine for a week.  But now it is doing it again. You will be driving, it will fade out, you pull over start it back up and you are on your way.  There is a pretty large exhaust leak at the joint from the section of pipe from the bottom of the manifold to the catalytic converter.  But I can't see how that would affect the motor in this way. I will be replacing that pipe section this weekend.  In the meantime, is it possible there is actual debris in the tank?  If so, is there any way to remove it without actually removing the tank?  How can I be sure it is this?  The car ran fine for 4 days and then starting acting up this afternoon again.  What do you recommend?

Answer
Hello,
exhaust leakage problem is a big problem, you have to solve it as you said,
but this problem seems as if it is about fuel system,
and your thinking is very good about debris in the tank,
unfortunately the only way is to remove the tank to clean it completely,

regards//vedat