GUNSMOKEJAE

I had a battery doing weird things 

when tested the battery itself not connected to terminals 

reads 12 to 12.1 volts 

while connected to terminals 

reads 

11.8 volts 

now when I try start 

the car wouldn’t turn over or anything so I tried jump starting via connections in engine bay 

no success 

so I jumped from battery directly in the boot 

the engine would crank but wouldn’t start again and would just wind over and over slowing down the longer I tried to crank it over 

I then checked the fuses 

fuel pump relay 

etc 

fuses are fine 

so I replaced the battery 

with a brand new battery now in the car still only cranks and won’t fully start properly 

just keeps winding over until I press start/stop button to turn car off ignition phase ????? 
 

is this a computer reset issue ? 
where I have program ECU with key to new battery as it’s (for some reason) not registering that a new battery has been connected ???