1996 Chevy Express van won't start Turns over and tries but it clicks in between and the dash lights flash

The dash light flash off and on while this is happening and the starting attempt stops also. Have tried accelerator to the floor when this happens also somtetimes it works. Just replaced computer modules and it worked for a bit?? Think maybe bad module???1996 Chevy Express van won't start Turns over and tries but it clicks in between and the dash lights flash
sounds like a bad batt. jump start it or try another batt1996 Chevy Express van won't start Turns over and tries but it clicks in between and the dash lights flash
It always amazes me how many people just throw parts at cars as they think that this will fix them. The only way to be sure something gets fixed is to diagnose the condition first. You are experiencing a condition by the sounds of the explanation that the motor is turning over slowly, stops turning over with some clicking and lights flickering by my take on it. This would indicate to me that there is a voltage supply problem to the starter. To start diagnosis do an AVR check which will check the strength of the battery and the amount of current draw that the starter is asking for. This will either tell you your battery or starter is weak or drawing too much. If that is the case with the battery, try boosting the van first to see if the symptoms go away. If they do, replace the battery being sure to inspect the battery posts closely for poor connections or corroding. Likewise to the big and small ground connections to the block and fender. I would also chase down the big positive battery cable to the starter to be sure it is not loose at the starter solenoid or worn through insulation that could ground to the block or somewhere else. If all that checks good, then look for a voltage drop in the ignition switch wiring or switch itself. Don't throw parts at it as that rarely works as there are too many things in here.