I have a 2010 Cooper S and my OBD reader returns p0001 p0300 p0303 p0304 and p0301. I have just replaced the sparkplugs. The check engine light goes on and off. Any idea on how to chase these codes down? I am guessing that the engine misfires could be caused by the p0001 -> "fuel volume regulator control circuit open". I did disconnect the battery when I changed the thermostat housing because I found it easier to get PCM wires out of the way. Help would be appreciated. Thanks.

 

Sounds like you may have a failing HPFP, have you checked fuel pressure numbers?

If MINI of Canada is under the same warranty as MINI USA:

You can call the dealer to see if your car is covered under the HPFP warranty, if so you'll get it replaced free of charge.

 

start the car and unplug the HPFP and see if the car dies or not. if it does, the pump is good.

 

If the pump is bad and I unplug it while the car is running, what can I expect?

 

When i did that on my 08 clubman s, the car remained running. When you give it gas it will shut off too.