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Anyone experienced this problem before?
F56 Cooper S from 2016.
Currently 80k miles, when cold start it runs fine,
when the rpm settles to 690-720rpm it feels like a 3 cylinder. Judders a bit. Having a solid lower engine mount you really feel the vibration.
recently i had a misfire on cylinder nr 2, changed the sparkplug. Problem solved. 2 weeks later (now) the idle is bad. Most of the time.. when you drive or rev it you don't notice anything. It has plenty power (stage 2) only the idle has a misfire code that is present when you read it out with torque pro. Fuel pressure is about 199-200 bar @idle. So are the injectors going out? Possible to check the injectors without dismantling them?
thanks
I'm not an expert, but it sounds like carbon buildup. It's a common problem on direct injection engines and sounds in line with the mileage and symptoms you describe. No joke, I think the remedy is to blast it with something that burns up (BMW uses walnut shells, I heard). I'm not sure the cost though. But from my knowledge, it's a common and know problem with the type of engine that the MINI uses.
These engines have not shown carbon issues, at least nobody has posted up horrifying pictures of all the crud.
Have you checked the coils, at 80K might be time for new ones. Swap a coil with #2.
Anyone experienced this problem before?
F56 Cooper S from 2016.
Currently 80k miles, when cold start it runs fine,
when the rpm settles to 690-720rpm it feels like a 3 cylinder. Judders a bit. Having a solid lower engine mount you really feel the vibration.
recently i had a misfire on cylinder nr 2, changed the sparkplug. Problem solved. 2 weeks later (now) the idle is bad. Most of the time.. when you drive or rev it you don't notice anything. It has plenty power (stage 2) only the idle has a misfire code that is present when you read it out with torque pro. Fuel pressure is about 199-200 bar @idle. So are the injectors going out? Possible to check the injectors without dismantling them?
thanks
Gotta ask stupid question but did you verify plug gaps before install? I ask because after I installed colder plugs, I made the mistake of ASSuming the gaps were correct out the box like most plugs are today. With my stage 2 Evolve tune, when I got on it, the ECU threw misfire codes and put me in limp mode. I pulled the plugs and they were WAAAAAY off - gaps too large. Corrected gaps and issue resolved.
Remember: troubleshoot basic stuff first...spark, fuel and air. Could be something simple or could be something more involved but check basic stuff first.
Gotta ask stupid question but did you verify plug gaps before install? I ask because after I installed colder plugs, I made the mistake of ASSuming the gaps were correct out the box like most plugs are today. With my stage 2 Evolve tune, when I got on it, the ECU threw misfire codes and put me in limp mode. I pulled the plugs and they were WAAAAAY off - gaps too large. Corrected gaps and issue resolved.
Remember: troubleshoot basic stuff first...spark, fuel and air. Could be something simple or could be something more involved but check basic stuff first.
I swapped the coil 2 weeks ago to check what was bad. But after swapping it, the engine still ran on 3 cylinders. 1 spark plug was bad, strange because it ran 7k miles. Maybe even less. Oil is changed every 6k miles. Engine performs great on acceleration.
idle it can be rough. What i've noticed is that the thread on the nr 2 sparkplug is a little bit wet/oily compared to the rest of the 3. The electrode is clean brown/black. Going to try an injector cleaner first. Because i don't know what's causing the bad idle at some moments. What's the correct gap? I'm using the NGK SILZKBR8D8S. Which i already changed 3 times over the time of the car. And now they're failing on the car? A point to be said is that the car is stage 2 but at the moment the catalytic converter is installed. (MOT) but this is temporary
Last edited by ClubsportF56S; Jan 28, 2020 at 10:28 PM.
Replaced 4 spark plugs. Idle still the same (little rough) I've noticed today that the cat smells bad. Tomorrow replacing it with the decat. That could be it, pretty sure. Updating tomorrow
I swapped the cat with the decat.
Engine runs normal and goes alot better 😁
the combination of the AWE intake with the decat is a symphony 🔥
conclusion : do not run the cat for more than 2 weeks when it's mapped with a decat. Temperature/backpressure will cause the spark plugs to go bad and it is going to misfire. It's also bad for the catalytic converter. It started to smell bad. But after looking at the element inside, luckily no sign of wear
These engines have not shown carbon issues, at least nobody has posted up horrifying pictures of all the crud.
Have you checked the coils, at 80K might be time for new ones. Swap a coil with #2.
These engines can have carbon build up issues just the same as the 2nd gen, although not as aggressive and severe, it still does have it. I've taken the B46 motor out of the car at 66300 miles and removed the heads already. The carbon build-up is on the valves and on the piston face. It's harder to remove the piston's carbon build up than the 2nd gen's in terms of effort and amount of chemicals used. Carbon build up does happen, and it does affect idle quality if it's too severe.
These engines can have carbon build up issues just the same as the 2nd gen, although not as aggressive and severe, it still does have it. I've taken the B46 motor out of the car at 66300 miles and removed the heads already. The carbon build-up is on the valves and on the piston face. It's harder to remove the piston's carbon build up than the 2nd gen's in terms of effort and amount of chemicals used. Carbon build up does happen, and it does affect idle quality if it's too severe.
Would love to see some pictures if you have them. So you just would use chemicals instead of blasting?
