I just bought an 07 Cooper s. When I went the car started right up and drove. He said the high pressure fuel pump was starting to go and would need to be replaced. I got it home and tried to start it the next day and it would start up and then shut off and sometimes when I gave it gas while starting it would start up and stay running. It would run super rough though shaking the whole car and the car only has around 90 psi of fuel pressure. When you give it gas it does nothing. I changed out the high pressure fuel pump and gave it an oil change and fresh tank of gas. After changing out the hpfp it took a few tries before the car started. It started and ran great. Went to the store and turned it off came back out started right up. I drove home and parked it. I went out early evening the next day and we still had the issue of it starting up and shutting down. Any ideas would be much appreciated!

 

Based on your own diagnostics i would suggest testing the fuel pressure again, and see how you make out from there. You getting any codes? Engine Lights, there must be something that can help diagnosis this.

 

When I tested the fuel pressure yesterday I was only getting mid 80s when the car would want to start. Once it started up the fuel pressure went to 700s. With the car off the low fuel pump was between 80-100 psi and with the car running it is 700-780 just idling. There are no check engine lights on. When the car is wanting to start but will not I can give it gas and sometimes get it running from there but it runs super rough shaking the whole car and has no throttle response. Come that time there are still no lights on the dash or the code reader. The fuel pressure then is around 150-200.

 

hm, you could check the spark plugs. does it run and start fine once it warms up? there is an in-tank fuel pump. I would keep checking your code reader, check for codes as often as you can. eventually there should be at least a pending fault

 

Hpfp