95 bonneville ssei spuddering?

Hmm I don't know what the skreeting sound might be, but your lack of power and spuddering is most likely do to an ignition problem. This van has a V6 and GM V6's use a waste spark system. Many times a spudder or lack of power is due to a failed ignition control module or coil pack. If you have a failed coil pack you should replace the ignition control module as well because it most likely has damaged the ignition control module anyway.

The first thing you should have done was go back to the gas station and complained. If you can prove you bought the gas there, the station is on the hook for the cost of repairs. They have insurance to cover it. Then you take it to a shop to get it fixed.
You may have to change the filter screen in the tank since there is no external fuel filter on the car. And that injector may have to be replaced too.

Not to cause back firing,spudder

It will effect the performance some,
as it reports exhaust gases & that is
used to adjust injector timing

GO TO AN AUTOZONE OR ADVANCE AUTO PARTS THEY WILL READ CODES FOR FREE. IT IS IMPOSSIBLE TO DIAGNOSE/REPAIR WITHOUT SCANNER ASSISTANCE

First of all, If you recently bought gas from a place you've never been to before, drain out the old gas, and put in a fresh tank from somewhere you trust. You may have water in the tank. After that, if that doesn't solve the problem, or you trust the place you bought from, go ahead and check all your external gas filters. If that doesn't solve it, I think that's when you're right: It's either the fuel pump, or the fuel filter, and in modern vehicles, both are in the gas tank, and both are very difficult to get at.

is it a series 2 or series 1 3800

good chance with that problem you were close most likely a misfire will cause that. it would be either your spark plugs or coil pack. also make sure your vacuum lines are good and air filter is good. also bad gas can cause that problem. the worst outcome would be your throttle body going out on you.

Check vacuum lines and hoses. Breaks in your vacuum lines will make your car feel like its choking. I had 3 rubber connectors go bad and my car shut off every 15 minutes (summertime) Stopped when I check all lines and replaced bad connectors. Your fuel pump might be bad as well. Check your ignition coils (maybe icm too)

it could be the oxygen sensor for the mazda and the blazer you have something wrong with the distributor cap

Most likely caused by a failing coil pack. The dealer can do what is called a stress test on them to see if they are bad or not but this is pretty labor and time extensive because they have to be removed one at a time to test them. If you have access to a scan tool that will read mode 6 data it may show which cylinders are showing some miss fires and you can try and just replace the ones that show a miss fire and see if that works.