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JCW GarageInterested in John Cooper Works (JCW) parts for your 2nd Generation MINI? This is where JCW upgrades and accessories for the MINI Clubman (R55), Cooper and Cooper S (R56), and Cabrio (R57) MINIs are discussed.
2010 R56 S 95k miles. Had the car for 7 months and 4k mi. New (real) NGK plugs on 7/20/20 82800mi, good gaps still. No codes. Data logged with Bimmerlink when cold each time. In the last couple of weeks I have had a misfire when cold on plugs 1-2-4. I have obtained a used set of coils (?mi) and swapped them out 1:1 from the other car, I will spare you the swapping details going forward but nothing changed. I have swapped plugs around and nothing changed. The hesitation and missing is very slight is more pronounced when cold but imperceptible when warm. Misfire happens at highway speeds. The HPFP will get down to 550psi at 122deg misfire cyl 4. but will get to 650-700psi when cold with cyl 1-2-4 misfiring. The misfires on 1-4 also happen at 1200-1600psi with the temp at operating. Cyl #3 NEVER fails... I do not know the status of the fuel filter but always use top tier fuel of Shell/QT. Complicated huh? Yeah I know its a problem child/mini life. Going to Mini's on the Dragon in 2 weeks need this sorted.
Who agrees its dirty or failing fuel injectors or potentially HPFP?
Last edited by FrankMstein; Apr 24, 2023 at 09:34 AM.
Well as soon as I say #3 doesn't misfire it did at lunch today on the way to get BG 44K...FML. This time it was with #2 at the same time. Even as high as 1600psi on the HPFP. WIll test for intake leaks then scope out the valves next I guess if the 44K doesn't work.
Last edited by FrankMstein; Apr 24, 2023 at 10:10 AM.
2010 R56 S 95k miles. Had the car for 7 months and 4k mi. New (real) NGK plugs on 7/20/20 82800mi, good gaps still. No codes. Data logged with Bimmerlink when cold each time. In the last couple of weeks I have had a misfire when cold on plugs 1-2-4. I have obtained a used set of coils (?mi) and swapped them out 1:1 from the other car, I will spare you the swapping details going forward but nothing changed. I have swapped plugs around and nothing changed. The hesitation and missing is very slight is more pronounced when cold but imperceptible when warm. Misfire happens at highway speeds. The HPFP will get down to 550psi at 122deg misfire cyl 4. but will get to 650-700psi when cold with cyl 1-2-4 misfiring. The misfires on 1-4 also happen at 1200-1600psi with the temp at operating. Cyl #3 NEVER fails... I do not know the status of the fuel filter but always use top tier fuel of Shell/QT. Complicated huh? Yeah I know its a problem child/mini life. Going to Mini's on the Dragon in 2 weeks need this sorted.
Who agrees its dirty or failing fuel injectors or potentially HPFP?
If you didn't replace those plugs I would have done that just on principle with 82K miles on them.
I have no info on what the fuel pressure should be but you need to know and confirm the fuel pressure is within spec. Proper fuel pressure is critical with any engine but with a direct injection engine even more so as the high fuel injection pressure ensures the fuel is injected at the proper time and the fuel from the injector is properly atomized for proper combustion.
Be sure the check the coolant temperature and intake air temperature readings cold are correct. If one reads say too high the engine controller at cold start can fuel the engine too lean and misfires can be the result.
If you didn't replace those plugs I would have done that just on principle with 82K miles on them.
I have no info on what the fuel pressure should be but you need to know and confirm the fuel pressure is within spec. Proper fuel pressure is critical with any engine but with a direct injection engine even more so as the high fuel injection pressure ensures the fuel is injected at the proper time and the fuel from the injector is properly atomized for proper combustion.
Be sure the check the coolant temperature and intake air temperature readings cold are correct. If one reads say too high the engine controller at cold start can fuel the engine too lean and misfires can be the result.
Thanks. The plugs were replaced at 82.8k they have 13k on them, hence the non-counterfeit (real) comment. I datalogged with the temps, however it misfires at ALL temps, just more at initial start.
Thanks. The plugs were replaced at 82.8k they have 13k on them, hence the non-counterfeit (real) comment. I datalogged with the temps, however it misfires at ALL temps, just more at initial start.
Ok.13K miles on a set of plugs is not is probably not sufficient to condemn them. Just be sure they are gapped correctly.
Did the data logged temperatures appear to be legit? At cold start they want to be close to ambient. As the engine idles coolant temperature goes up about 1F every second or two. Give or take. What you want to see is the temperature goes up at a reasonable constant rate as the engine idles. Intake air temperature should remain about ambient though of course as the engine warms up this can heat the intake system.
But you are looking for big (relatively speaking) discrepancies in temperature readings.
While I focused on the temperatures I think the fuel pressure still remains suspect #1. I will continue to think this until you come up with something official that says the readings are within spec.
The HPFP ranges from 550-1600psi and it misses at all pressures and temps all cylinders now. It is just more pronounced at cold temps. Sometimes multi cylinders at all temps and pressures, less on #3. Believing it is a DME as @ohmrion said. I scoped the throttle body and intake and it is "brand new" clean. I assume the valves are too. Another point is that the cheap new valve cover I got from ECS is leaking oil all over the cover at the idle side (timing chain end) of the cover and this started near the same time as the missing. I removed the hose and there is a flood of oil in it along with more consumption.
Last edited by FrankMstein; Apr 28, 2023 at 09:20 AM.
It is cheap and easy to just pull the intake manifold and have a look at the intake ports to see how much carbon is in there. Certainly MUCH less expensive than sourcing a DME and having it programed to the car.
Are you getting misfire codes? Or any codes at all?
Still... I would be checking the intake for carbon build up, and maybe getting a scope to check the cylinder conditions. At almost 100k miles, you're probably due for cleaning. Worst case, the carbon has damaged something in the cylinders. I would be exhausting all other possibilities before getting a new (or used) DME.
Yeah, looking at removing the intake and possibly installing a catch can on the right side tomorrow. This is my wife's car and she doesn't drive it hard enough to clean the valves off. Not sure why the idle side is so oily now. I just don't want to disturb anything as we are leaving to go to the Dragon on Wednesday.
After 1 can of BG 44K and used 1/3 of the tank at 90mph AND two seafoam applications it "funs" a lil better. Less missing when cold and smooth idle. It still misses but not as much. The pics are before. I will plan on pick/blast/seafoam the intake as well as a catch can after the Dragon run this w/e.
After 1 can of BG 44K and used 1/3 of the tank at 90mph AND two seafoam applications it "funs" a lil better. Less missing when cold and smooth idle. It still misses but not as much. The pics are before. I will plan on pick/blast/seafoam the intake as well as a catch can after the Dragon run this w/e.
First car in which intake coking like that was a possibility was my VW Golf TDi. The combination of oil/water vapor from the crankcase ventilation system and soot from the EGR could combine and over time build up so bad to restrict engine breathing.
I'm loathe to have to subject the intake/head intake ports to any physical cleaning unless absolutely necessary and to keep this from becoming necessary I changed the oil every 5K miles (vs. the 10K miles VW scheduled) and avoided driving the car around like a big rig with RPMs never breaking 2K. Put 150K miles on that engine with no build up.
For my cars with direct injection gasoline engines and this currently includes my 2023 JCW (and my 2023 BMW M2) I will change the oil every 5K miles and avoid super low RPM usage. And every so often -- 250 miles before each 5K mile oil change -- use a bottle of Techron to remove fuel injector, intake valve, and combustion chamber/piston top deposits.
