R53 Won't Start After DDM Intake Install
 

After installing a DDM CAI in my 2002 Cooper S the engine will crank but never turnover. I believe it may be an electrical problem since I had to unplug the ECU for the install. I removed both terminals from the battery before doing any work. When I turn the key to position one, the temperature gauge goes all the way up and the red light glows. The oil light and battery light also glow. I followed the instructions from the DDM website so I am not sure what went wrong. Has anyone experienced a similar issue?

recheck your battery and ecu connections.

What he said. Plus, try unplugging everything again including the negative battery cable. Turn the key on to discharge any electrical capacitance stored in control modules. Turn key back off. Reinstall negative battery cable. Reconnect both ecu connectors and ensure that they are seated properly. While it is unplugged ensure that the ECU has no bent pins. Check throttle body connector.

Once everything is plugged back in try again at starting. If your engine is cranking slowly due to all the cranks with no start, then recharge the battery or jump start if necessary. Probably a simple electrical issue like loose battery cable, bent ECU pin or connector that is not properly seated.

Looks like the ECU wasn't completely locked in. Thanks a lot! Mods can lock this thread