Car would run weak for a couple hours then die but crank and after a couple hours would start back up but after driving would do it again. Low fuel light comes on sometimes and eventually stopped running but still cranks. 89 olds 88--3.8

At best, this would really be hard to find, since you can drive it hours before it happens. You could start by pulling all the fuses one at a time check them and put them back in. This gets rid of corrosion contact problems. You can also do the to all the plugs. Sounds like you have a heat up problem. Some thing in the electrical system is getting hot and loosing contact. Things that would kill the engine would be , the ignition switch, the map sensor, the mass air flow sensor, And the engine control module. Parts inside of these can heat up enough to loose contact. Your's is going to be a hard one to find. Until the part completely dies.

Could be anything electrical. A weak relay, the coil pack or ignition module, and so on.
You'll need to figure out what is loosing electrical power when it fails to start to know what to test. You might start with the fuel pump relay.

It sounds like a clogged fuel filter

possibly 4 things 1 bad ignition coil heating up then breaking down,2 clogged fuel filter,3 weak fuel pump,4 bad throttle position sensor or map sensor to check sensors simply put on hand held scanner and look for codes. replace fuel filter replace coil pack along with tune up plugs wires put fuel pressure gauge to see if fuel pump is working properly

Sounds like you need a fuel pump. There is an access panel in the floor of the car to get to the pump.

mcdevito75 Here, It"s possible the ignition Module is going bad, no way to test and if so, one day the car will not start at all.----------It can also be a vapor loc, wher the fuel is evaporating before it reaches the cylinders. Best Bet, have your local shop check both these items.

normally a speed control sensor can solve this problem, but also check the crank senson.

First off, I think you bought a raft of stuff you didn't need on that repair job! The sound of it at this time is that probably the fuel pump is about gone.You need to measure the fuel pressure (engine running) at the fuel rail (the test port looks like a tire valve) above the injectors. The pressure should be in the 45 to 55 PSI range. If the pump is toast, it will be much lower. The pump resides in the fuel tank. You probably have the check engine light on. If the code(s) are read out with a scanner, it will likely point to the fuel pump.

You have a cam or crank sensor that has gone out.

it sounds like it the crank pos. sensor