I have 2 ALL4S- If you used anything other than Beru or NGK plugs no matter what Autozone or the book says change them and gap at 8mm if stock tune or 6mm if you have any HP adders' such as a tune or JB+. These cars are very picky about plugs and Gap. Also only use a top tier fuel 93 if you can get it. such as Shell, BP etc.. no discount or off brand fuel in these cars. Lastly you don't mention how many miles, check the air intake tube, I saw one last week that was filled with debree blocking about 50% of the airflow.

 

ke3ee, thanks for the input. I checked the air intake, and everything looked fine. The car has roughly 65k miles. I've only used high grade gas in the past, but who knows what the previous owner used. I've decided to go to the dealer and purchase "factory parts" and see what they end up giving me. I'll then compare their product to what I installed. Fingers crossed that this will resolve the issue. If nothing else, at that point I'll have "factory parts" on it and if the HPFP goes out, they'll replace it for free. Will post again in the coming days.

 

Rumcuredcrook, what was the final outcome to your challenges with the misfiring? I'm now facing the same symptoms under the same conditions with my 2014 Countryman S All4, about 48K miles. Was fine when I bought it at 36K miles, started doing this issue around 45K or so.

Thanks!

 

I finally sold this car to Carvana today. I know most people on this thread are Mini enthusiasts, but I will personally never buy another BMW product again.

So the misfire was due to incorrect plugs and coils being installed. I think I spent around $500 or so to correct the issue. It drove fine for about 3 weeks and I thought all our problems were gone. A minor headache, but hey, these things happen.I wish that was the end of the story.

I wouldn't ever call myself a mechanic but I would say I know warning signs when I see them and know my general way around a vehicle. I've done dozens of moderately difficult repairs on my own over the years.

So to diagnose the incorrect plugs, I took the vehicle back to the mini dealership. That week I also received a thermostat housing error code that came and went. The car was inspected by the mini dealership where I brought up the thermostat housing code. The mechanic said he saw no signs of an issue.

Fast forward a couple weeks and my wife is driving down the road when the vehicle begins to shake violently and she starts getting error codes flashing at her all over the dashboard. She immediately pulls off to the side of the road and calls me to tell me what was happening.

I tell her to shut the car off and I call a tow truck. I have the vehicle towed straight to the mini dealership where they tell me the engine is completely shot due to....you guessed it, a leak in the thermostat housing.

At this point we are about 6K miles outside of the factory warranty, go figure. I bring up the fact that I had mentioned the thermostat housing error code to the service member just a few days prior to the incident, when they told me they couldn't detect anything. They offered a 10% discount on the repair. They wanted somewhere in the ballpark of $14K to replace the engine. Thanks, but no thanks. I told them they could go kick sand.

Found a good, used, factory engine with roughly 48K miles on it and took it to a certified BMW mechanic just outside of town. Still ended up costing me around $6K. This vehicle had under 70K miles on it.

I've never heard of such a thing, especially with little to no warning signs. No leaks in the driveway, no indicators prior to the day of the incident, and the mechanics at the mini dealership not being able to detect the thermostat housing leak just days before the engine went out as a direct result of said leak - despite me telling them about the error code.

The whole thing was unreal. Best of luck to you. I truly hope no one goes through the same hell this car brought us. I would start with making sure you buy the spark plugs and coils directly from the dealership. This will cost you more than you want to pay, but that seemingly solved my problem for a few weeks. Hopefully your troubles end there. Good luck.

 

Sorry to hear about your bad experience. My wifes 2012 Countryman had the thermostat housing replaced under warranty. The dealer paid for a rental Jeep Cherokee for 9 weeks waiting on the thermostat housing. For the record I have had 7 BMW's and my wife is on her 3rd MINI (2002 Mini, 2010 Clubman and now a 2012 Countryman All4S). They are picky on coils and plugs and you should only use OEM. She had a random misfire on cylinder 1 under hard acceleration around 46k miles. The culprit was the spark plug. Take a look at the photo and see if you can pick out the spark plug from cylinder one.


One of these plugs is bad

 

 

The misfire was from incorrect spark plugs. I bought replacement Beru's from ECS. When I removed the factory plugs they wete Beru with no MINI name on them. ECS will be at least half of what you will pay for them at the dealership.