Hello All,
I have a 2012 R56 S automatic
late in the winter this year I put my mini and quick jacks to do some mods. coil overs, sway bars, and a fuel filter. 3 weeks ago I finally got around to finishing the car. I know it took forever I work crazy hours.
so I found my battery tender fried the battery it was not in the car at the time of destruction. so I got a new AGM battery from my local stealership as they had no regular batteries.
the car will crank but not start. I replaced the spark plugs, the relay in the engine compartment against the firewall, and the relay on the JBE. sent the JBE to detroittuned and was just informed that the JBE is fine.
Also, the only code I get is for the cas system which the techs at Mini say to ignore. Also, it will run on starting fluid but barely. Any Help would be GREAT.

 

So, with starting fluid the car starts and runs? But then struggles to when that happens? If that is the case the mods you did has one to with the fuel system. I Would check the fuel filter installation, making sure that you didn't inadvertently create a restriction.