The Mini Issue -Random Misfiring and Suddenly dying. Mini Cooper S P0300, P0301, P0302, P0303, P0304

My 2010 Mini Cooper S Clubman bad solder on fuel pump relay on the interior fuse panel. Random misfire codes (P0300, P0301, P0302, P0303, and P0304), pending and/or stored. Suddenly dying without any symptoms or warning, no codes afterwards.
Video shows you how to fix it. I hope you the video is helpful. Please leave a comment if it helped you.

[@user-ix9yu3wq6w]

Whenever people start talking about their car stalling on the mini forums I'm going to just post a link to this video from now on. Had the exact same issue in my 2013 Cooper

[@thebaldguy1466]

Did it help your Mini?

[@user-ix9yu3wq6w]

@@thebaldguy1466 indeed. Mr Cooper broke down the first day and this was diagnosed as the issue by the dealer the next day. They ordered a brand new BCM but it is coming from Germany and won’t be here until July 22nd. So I bullied them into giving me the part and I fixed it myself. Been working great.

[@thebaldguy1466]

Awesome. I do think this was one of my problems, but not the only. I later had similar problems. My intake valves were very dirty. I hope your Mini is fixed. If not, it might be the intake valves.

[@user-ix9yu3wq6w]

@@thebaldguy1466 fingers crossed! I’ve been slowly but surely doing routine maintenance on him. Next step is new spark plugs and air filter

[@pansolo]

Hi, do you know which relay on this board is for the blower motor (A/C) ? I believe it is R4 but what is the model number for the relay? Appreciate any guidance

[@thebaldguy1466]

I’m not sure. I wasn’t able to find it. Sorry.

[@hogi99]

Not sure why cutting the pins became the preferred method, unsoldering one side would be better I think. 🫣 It also seems suspect to resolder but not replace the relay? There's a reason that connection overheated in the first place.

[@koshthekernel]

Hi. We have a similar problem. We took it to a mechanic and they replaced both gas pumps. The main one and the one in the tank. Still getting the same stalls and the Cooper will die. Only after several minutes it will start again. Engine light wil come on. The techs at the repair shop couldnt duplicate it. But every time we took it for a spin to go to Walmart, it will do it. Whats creepy about it was it will stall and die exactly in the same street. It did it 4 times. Same symptoms. We have driven ot 130 miles on and off and hasnt done it yet, but Im afraid if we go to Walmart it will do it again. The code would read P0087 Fuel Rail / System Pressure too low. Do you think we have the same issue? A reply would be appreciated....😉

[@thebaldguy1466]

I’m not a mechanic, but based on my research and limited understanding of the fuel system. The fuel pump relay controls the fuel pump, which supplies fuel to the high pressure fuel pump. The HFP is mechanical powered by the camshaft. So if the HFP isn’t being supplied with fuel, then it could throw a P0087. Long explanation short, it’s possible it’s the fuel pump relay. My Cooper was randomly dying too, but without any codes.

[@andrespaez6493]

Question is it possible to see the damage to the solder before cutting the JBE open?

[@thebaldguy1466]

It was very difficult to see it. But I was able to see that it was different than the other solders.

[@superduper6379]

how did you get the main power wire to the fuse box off? 5:31

[@thebaldguy1466]

Sorry I didn’t write back sooner. I just pried it off. It slides straight off. The wire itself is held in by two pieces of plastic.

[@stevetilbrook3402]

Get these cash pits running and sell them.. My GF's was throwing codes and it was just a pcv cap and membrane but valve cover it was perched on cracked when I took it off. Theyre made to break. I changed the battery and a control module lost coding then the lights wouldnt go on and the doors wouldnt lock the hazards wont stop either.. Dump these pieces of trash pronto.

[@bobbys6364]

Why not desolder the connecting pins rather than cut them?

[@thebaldguy1466]

I think it would have been harder to not cut them. My soldering skills are not very refined.

[@xnoitulos]

FWIW, In another video on this a guy in the comments said he was going to try to do it that way, but found the pins are not just soldered but also have some waterproofing or protective coating, so he ended up cutting them like this.

[@gregrasmussen9915]

Were you getting the misfire code from the same cylinder or was it from random cylinders?

[@thebaldguy1466]

They all appeared random. I had more misfires in cylinder four, but I was getting misfires in one and three also. I never recorded a misfire in cylinder two, I might have missed it. I didn’t check for pending codes all the time. Sometimes there would be multiple pending misfire codes in different cylinders and other times there would only be one. When the check engine light would come on, there would be one or multiple misfire codes in different cylinders, along with pending codes for misfires in different cylinders. I hope this helps.

[@gregrasmussen9915]

@@thebaldguy1466 thanks, I am getting them only for cyl 1 and it’s not the injector, coil or plug, and it has great compression. My next move was to look into the DME as I have seen diesels with similar issues with injector drivers that have cracking solder. Then when I saw your video it was the only one I came across that dealt with electronics as a cause. Thank you for posting it.

[@thebaldguy1466]

@@gregrasmussen9915 thanks for watching. Good luck finding the issue.

[@suttoncurt]

@@gregrasmussen9915 did you ever solve your cylinder 1 misfire? My problem is exactly as you describe but the misfire will go away after restart.

[@RasmussenEquipment]

@@suttoncurt It was the DME, I bought a used one on eBay with the same part numbers then sent it along with my old one to a guy I found on eBay who reprogrammed the used one with the info from my old one. She is all better now.

[@RudyGerardo]

I did all these steps, and it ran fine for 10 minutes then stranded me again. Will post later when I find out what the root cause was.

[@thebaldguy1466]

I started getting misfire codes again. I didn’t get stranded. For me it was an issue, but I don’t think it was the issue. I have since cleaned the intake valves by hand with picks and intake valve cleaners. The intake valves were covered with carbon buildup. I cleaned the fuel injectors which were dirty too. Unfortunately, I didn’t check how well they were working prior to cleaning the injectors. I cleaned the VVT solenoid. I found my timing was slightly off. I replaced the belt tensioner with a genuine mini tensioner. The old tensioner was not as strong as the new one. I replaced almost every rubber seal/gasket on the engine. I have driven 250 miles so far, no codes. I’m going to do a fuel treatment, intake valve and turbo cleaner, and then an oil treatment. I hope it was due to how dirty it was. Otherwise, it might be a bad DME like Suttoncurt had commented about. Good luck.

[@victoralcantara2767]

Did that repair solve your problems?

[@victoralcantara2767]

I have the same issue 😕

[@thebaldguy1466]

It fixed the problem for like 10 thousand miles. It has started giving misfire codes. It hasn’t died on me again. I’m in the process of taking it apart, cleaning it, and checking the condition of components. I will definitely post a video when I figure it out.

[@Timber81]

Clean your throttle body if you haven't already. It will cause stalling with no codes.

[@Timber81]

I took my fuse panel apart and found no burnt or loose (Cold) solder. Though some have had burnt solder on the fuel pump pins.

[@Timber81]

Also, your Vanos or VVT solinoids might be dirty or failing. Easy fix

[@bliedblad]

Is that a mustache?