2010 Mini S R56

A few months ago car died 150 miles into a ten day trip. Towed home and got to work. Noticed coolant pooling on trans housing. That along with 6 years of trouble free use I jumped in and banged out a ton of misc. stuff as well as all the stuff I broke trying to fix other things. Anyways here's a list of everything that was done:

Valve cover/PCV and gasket
Plugs
Coils
VVT solenoid
Coolant pipe
Thermostat/Housing
Battery
Turbo coolant line
Fuel filter
Water pump
Crank seal
Timing chain kit
Vacuum pump
Lower sprocket
cam position sensor
crank shaft sensor
Intake boot
Oil change

Since replacing these items the car runs great and smoother than it has in a long time but now the problem is as follows:

Starts and runs perfect. Will run this way from a few minutes to a month then suddenly loses power, runs extremely rough and dies. It runs so horribly it will not start again. If I clear the codes it will fire up and run as smooth as a sewing machine and the random "countdown" starts again.
Temperature does not seem to make any difference. Sometimes it will happen after hours of highway driving, sometimes right after I start it and as I'm backing out of the garage. Sometimes it will happen running 75mph down the road, sometimes sitting at a light. I have found no correlation to any specific action or condition. I carry a cheap Foxwell scanner in the glove box to reset it when it happens. Little weird when you have to do it in the drive through or in the middle of an intersection but hey, it works every time.....so far. If anyone has had an issue similar to this I would love to read your experience or if someone has the magic fix bring it on.

I will post pics of the codes last time I scanned it after I find them on my phone.

Thanks

 

Have you checked all those vacuum lines......Check the intake hose....check the hot and cold hoses....the hose on the passenger likes to come undone
check the clip....

 

Post the current BMW codes and the ones you cleared.

 

^This. Post the code you get when it start running crappy.

Based on symptoms, my gut would say high pressure fuel pump. If that is what you had replaced, which one did you go with? Cheap aftermarket, or reputable original equipment pump?

 

Here are the codes before I cleared them.
272A - DMTL solenoid
2773 - DME Combustion misfires, cylinder 1
2777 - DME Combustion misfires, cylinder 3
277B - DME Combustion misfires, cylinder 4
277F - DME Combustion misfires, cylinder 2
2783 - DME Combustion misfires, several cylinders
2A75 - DME Oxygen sensor after catalytic converter: Ageing

Quick scan faults:
Engine electronics, DME
Stability system - EBC 450 ABS-DSC (ABS wire came off at Left front)
Drivers side footwell module - FRM
Automatic heating/air conditioning IHKA

In response to one members question, I have not changed either fuel pump yet. I have only changed the filter in the tank. I would bet it was the original filter. As far as parts go I buy from BMW/MINI through my account or aftermarket through FCP Euro based on their recommendation's. If I do the HPFP it would be from MINI.

Thanks again.

 

You've got misfires in all 4 cylinders; I'd suspect a timing issue based on the list of repairs/maintenance performed. Suggest a cam/crank correlation test with a lab scope.

 

I like the idea, but would a mechanical timing issue fit with an intermittent problem?

 

No. Notice you lost coolant at one point. The cooling system only holds 1 gal of coolant, and these engines tend to drop valve seats when overheated. I had an intermittent misfire in cylinder 2 and it was a loose valve seat. What happens when the engine is misfiring and you disconnect the inlet camshaft sensor?

 

I will have to wait until it fails again for the camshaft sensor test. I was very, very meticulous during the timing chain replacement. Double and triple checked everything. I can't help but think it is a sensor or harness issue because a mechanical failure of almost anything wouldn't improve by clearing the codes, at least that what I rationalize. My assumption is something electrical goes haywire, the computer tries to compensate for it but goes off the deep end to where it wont run. I reset it and bring settings back to normal and it fires right up. It has 140,000 ish miles. I'm a little suspect of the LPFP or the relay. I'll start with the relay, and inspect for bad solder joints. How many miles do the injectors usually last? Just curious. Also, I've only ever run premium fuel.

 

Connect your scan tool under the OBDII protocol; look for STFT and LTFT numbers. What are your numbers at idle?

Also, after reading more of your initial post; when you get a misfire BMW/MINIs will disable the injector for that cylinder so you don't contaminate the catalytic converter with too much unburnt fuel. When you clear the codes or shut off the engine; the DME will enable the injector for the misfiring cylinder until it sees misfires in that cylinder again.

What you need to figure out is what type of a misfire do you have; and that normally requires an experience tech with a lab scope to analyze the secondary ignition wave form.

 

When the issue occurs, do you always only recover ^these codes? Sometimes do you recover any different codes? If you're lucky, you'll eventually find an additional code(s) that will help pinpoint the problem.

Is there any chance that the EVAP system code (272A) could cause misfires in all cylinders?

 

I will be replacing the DMTL solenoid just because. I think it's the only code I get when the car is running good so I might as well. I'll post pre and post scan results next time it fails. Thx

 

The high pressure fuel pump will cause random misfires, then run OK after clearing codes…

 

Right, that's why I said to check your fuel trim numbers. If the engine is starving for fuel, the DME will drive the fuel trims way up, but if these are lean misfires, he should see an associated DTC for that problem. Checking fuel trims is a quick and easy check with a scan tool that will help point the diagnostic in the right direction.

However, I just fixed my sister-in-law's R56 (justa) that had sky high fuel trims and rough idle. There were no DTCs in memory for a faulty upstream O2 sensor. The first thing I did was drive the car; and punch it. If it was a fuel pump, the engine would hesitate and stumble; it didn't. So I looked a the MAF, and I was only getting 1.8 grams per second at idle. I compared that to another R56 and it had 3.6 grams per second at idle. Cleaning didn't help, so I replaced the MAF sensor and I was right back at 3.6 GPS. However the car was still running rough. (OBTW 125K miles on the car and all original O2 sensors). So, I pull up the upstream O2 sensor current PID on the scan tool and hit the intake with some propane. There was no change to the current reading. I swapped out the upstream (and downstream since they both had so many miles on them), and the engine was running great again, and I could see the fuel trims correcting. I was surprised that the DME didn't set a code for a faulty upstream O2 sensor.

One last thing; BOSCH is the OE supplier for the upstream O2 sensor; NTK is the OE supplier for the downstream. I once installed a brand new NTK upstream sensor thinking it was OEM, but it didn't work, and it was setting DTCs. Once I installed a new BOSCH upstream sensor, all was well again.

 

Double check the fuel filter O-rings. Very easily to twist the large o-ring. I agree it sounds like a fuel delivery issue and if it isn’t holding solid pressure, it will die.