Hi Everyone - my Mini has been acting up the last 2 days and I'm concerned its the High Pressure Fuel Pump.

On start up it will take a good 4, 5, 6 times to fully get started and when starting up it will idle extremely rough for about 1-2 seconds before completely stalling. Once it does get started and I begin driving, it doesn't seem to have much power loss, if any.

Is this something that's relatively okay to drive right now? The HPFP kit on ECS Tuning is not in stock and if I change the HPFP I want to change the Pressure Hose and Fuel Feed Line as well.

I got codes P3091, P0300, P0304, and P0301 as well as the Red Mini on a Lift icon.

I have a 2007 Mini Cooper S (N14) for reference.

Thanks in advance for your help everyone, this forum has been extremely helpful diagnosing issues.

 

When was the last time you changed the following: spark plugs, ignition coils, oxygen sensor (upstream). If you never did and your mini is more than 80k it is time to get those replaced.

 

Hey thanks for the reply - I'm at 99k and spark plugs were done less than 10,000 miles ago at the same time as a walnut blasting - I ended up ordering a new HPFP and the corresponding fuel lines, so I'll be swapping the HPFP this week - I'll look into the coils and 02 sensors next with a timing chain refresh.

 

Is there a way for you to measure the live stream data from the fuel rail pressure sensor, O2 sensor, and misfire rates? Is the timing chain "refresh" informed by broken components or misaligned timing marks on the cams?

My 3-year misfire (starting in 2016) was remedied 2 years ago by installing a wholly rebuilt cylinder head. A companion issue was 0 psi oil pressure. Despite misfire and no oil pressure, the car ran excellently in the city and highway (sustained boost without problem). I ran it this way for 3 years, even on 600-mile trips. I wanted it to break, so I could finally reveal the source of these issues. It never failed and got me everywhere at the "speed limit."

The only reason I was motivated to replace the short block and head was to do something to help celebrate my fallen brother's life (d 2019). Otherwise, I may still have done nothing to fox these elusive issues. These replacements fixed both issues that remained even after replacing the oil pump, timing chain, HPFP, fuel injector, coils, plugs, walnut blast years earlier, and other minor misguided remedies. It turned out that a valve guide and piston arm bearing were worn (sources of misfire and 0 psi oil, respectively).

Now, I run two oil catch cans, AEM methanol injection, Seafoam in the oil, 3000-mile oil change rate to prevent premature oil sludge and deposit-related problems. When I bought the car new in 2010, I bought all the low maintenance hype and extended oil change interval nonsense.

 

Kedu thanks for the reply - I have an interesting update.

I went ahead and replaced the HPFP on Monday, car started right up after install, I let it warm up and retorqued the line from the pump to the fuel rail per the Pelican DIY. I feel like I fixed the issue, car drove fine all week.

I was still getting a random misfire code, but I didnt feel the misfire, the car idled fine and I didnt feel any power loss - car was completely drivable and felt fine.

Im due for an oil change so I take it to my local mini shop today out of an abundance of caution for the P0300 misfire code and they tell me im Misifring on all 4 cylinders and that its the coils and they want to swap out the spark plugs as well. I let them do the work and the car drives fine home - 6 hours later I go to start it and it wont even start. Needless to say I'm livid - I brought the shop my drivable car on supposedly bad ignition coils and now it wont start.

I was charged $400 for the ignition coil swap for Bosch 0221504800 coils and spark plug installed - I feel absolutely robbed and now I have a car that doesnt start - Should I be concerned with the shops work? I double checked my HPFP install and I'm positive I did everything 100% Proper. Needless to say im livid right now.