If my car sits for 2-3 days, when I crank it, it will start and then stall out, maybe 1-3 times before firing and running properly. If i start it later in the day, it's fine. After researching, It seemed like it was the HPFP so I bought an aftermarket one (OEM is $1300?!?!) and replaced it.

The problem went away for about a week, but it's back. What else could be causing this issue? Perhaps carbon build up? What sort of reader can I use to see if the fuel pump is indeed bad. The dealer by me is shitty and wanted $300 to diagnose the problem and I tried to mention the HPFP had some sort of service bulletin, but they really didnt' care.

53K Miles, JCW. I do drive it hard.

Please help!

 

When did you changed the spark plugs?

 

^this^
it very well could just need new plugs.
What year is it? There is a warranty extension for the HPFP for some. 10 years or 120,000 miles.
I’m getting mine replaced tomorrow morning on MINI’s dime.

 

And the diagnosis for the HPFP should only run about $100 I believe

 

Plugs, coils, HPFP, Vanos solenoids will all usually throw some codes. Do you have access to an OBD reader? That is step #1.

Dealer $300 is a pure rip-off. Most of the semi legit dealers will quote an hour to diagnose and then apply it towards a fix or refund it if its a covered item.

 

Exactly what I what trying to say... but much more eloquent.
I meant to mention getting the codes read, that’s should be step number one for sure. Just be aware, unless you pick up something that will read the BMW proprietary software, it will not show all of the codes. I’ve seen it firsthand with my car in limp mode and the scan tool said no codes, but there were really 6 of them it couldn’t see. So if you have someone do it for you, don’t just go to AutoZone or whatever, theirs won’t see them. Check with a few Euro repair shops or BMW /Mini specific shops, some will read your codes for no charge.
Or you can buy something.... it is almost a must have with these cars. just to know what is going on with your car, and if you plan to do your own wrenching, having one is an absolute must. I have a Schwaben scan tool from ECS, or there are apps like Carly and a couple of others, but I’m not sure which ones are good. Somebody else will be able to point you in the right direction for the apps if you are after one of those.
The scan tool is a one time buy, but quickly pays for itself. Carly has a yearly subscription I believe, and I’m not sure about others. The cool thing about Carly is you can do some coding with it too.

Also if you want to monitor things like fuel rail pressure, boost, AFR’s and so on, Dash Command (Apple) or Torque (Android) apps are good for that. You can create your own custom gauge clusters or gauges. I have DashCmd and it works pretty well. It will show you actual fuel rail pressure, but something like the scan tool will let you watch requested vs actual fuel rail pressure..... a good way to see how well the pump is really doing.