I have a problem with my lumina that hopefully someone had the same
problem.

my problem that i am having is the car will crank fast then crank slow
like the battery is dying then it cranks fast and again and starts up but
with a backfire and idles rough.

i have replaced the computer (brain), crank shaft sensor o2 sensor,iac
value,speed control sensor and the igintion module and cleaned all the
grounds that i could find, even tried switching some relays around and
checked all fuses that i can find.
repaced spark plug wires and spark plugs,coil packs and check if all wires
are in the right spot and they are and pcv value checked the wires
connecting to the igintion module etc.
the battery is band new. never had a problem with the car until Novmeber
when it started to idle rough and now it likes to start with this problem
and sometimes won't start at all sometimes.

can anyone help me please
don't rule anything out thank you