Hello I recently bought an 2009 Mini Cooper S (R56) I got it with the check engine light on I had been sitting for a while so I thought maybe it was just the spark plugs. Well that wasnt the case.
codes I got are
p303
P300
P302
P304
p173b
I have recently changed the oil and filter and the spark plugs I checked the coil packs one was bad so I had fixed the problem. But unfortunately the problem still persists I'm not sure what else could be wrong other than a bad head gasket or a cracked engine head. It also appears that I'm leaking coolent but I havent located from where yet. Thanks for the help in advance.

 

The 300 codes are cylinder misfires. The 173b code is related to coolant temperature.

Did you replace all the coil packs, or just one? I always recommend replacing all coil packs as a set.

You might need to have the thermostat replaced, too.

 

Just to make sure: you have cleared the codes after changing the coil? To see if they come back?

For coolant leak: there are so many threads around that. Cross over pipe, thermostat itself, ... Mentioning where the puddle is will help.

For the codes the same: timing chain? Carbon buildup?