R56 Ugh! '08 R56 won't run unless MAF unplugged.

Discussion in '2nd Generation: 2007+ R55 through R61' started by ccain, Feb 10, 2018.

  1. ccain

    ccain Active Member
    Supporting Member

    Jan 5, 2013
    152
    56
    28
    Retired
    Ratings:
    +56 / 0 / -0
    #1 ccain, Feb 10, 2018
    Last edited: Feb 10, 2018
    Okay, a little backstory first.

    I was driving my R56 one day and I got an engine temp warning. I immediately stopped the car and had it towed home.

    The problem turned out to be that dumb gasket on the oil filter housing. I did a ton of research, spent like $800 + to get the gasket and all associated parts I'd need to replace to fix the issue (turbo oil lines, exhaust manifold gasket... etc. All genuine MINI parts), put the car in maintenance mode and went to town. Heck, I even went ahead and replaced the cooling fan with a direct MINI replacement.

    Buttoned every thing up, refilled and bled the coolant system...

    (side note, I think it's ridiculous to have to use distilled water with the BMW coolant! I guess this stupid car also requires Perrier Sparkling windshield washer fluid and a spritz of Ode de Toilet on the cabin air filter when replaced because apparently this car is higher maintenance than my ex-wife)

    I changed the oil, made sure I had everything hooked back up correctly using diagrams I made and photos I took before the teardown... etc.

    I went to start the car and it fired up and I guess it decided it didn't appreciate what had just transpired and then promptly died while making this odd whistling noise.

    Bear in mind the car started and idled fine as I drove it into my shop to begin repairs.

    I rechecked everything. Everything was in place and this thing should have ran. After about two days of troubleshooting, I then admitted defeat and had it towed to MINI of Escondido to have it fixed.

    Of course, the FIRST thing they recommended was the walnut blast (which I had just had done less than 10,000 mile prior) to which I rolled my eyes so hard I got brain damage, then gave them the go ahead to perform. After the cleaning, they basically undid everything I had done and reassembled everything with new parts. They ended up having the same issue I had. Surprise-surprise.

    After having the car for a week and a half and throwing another $1500+ in parts at it, they finally told me that the car would only run with the MAF unplugged and that the only thing left for them to try was to replace the ECU which would cost me an additional $2300 plus shop time.

    Look, this car is 10 years old and now we're bordering on repair prices that outweigh the current value of the damned thing. So, I declined and picked up the car, running with the MAF unplugged. It's gutless, the CEL is always on, and there is a whistle under acceleration.

    To me, the whistle and the fact that the car only runs with the MAF unplugged indicates a vacuum leak somewhere.

    I left it as is and have driven it around town a bit, but now were at the point where the tags are due and it needs to be smogged.

    Californina won't smog the car with the CEL on and now I'm stuck with a car I can't
    A: Sell as is.
    B: Get smogged.

    So, I am left with the fact that I would have to place the car in "non-op" status at the DMV. At this point, the only thing it's good for right now is setting it the front yard, filling with dirt, and planting flowers in it -OR- donating it the the Marine Corps base down the road to use as target practice for their Howitzers. I guess it would make a decent boat anchor for a shrimp boat or something... I dunno.

    Can anyone point me in any direction as to what I can look at or do in order to get this dumb little car back up and running?

    Thanks!
     
  2. Zapski

    Zapski Well-Known Member

    May 4, 2011
    2,098
    887
    113
    Columbus, OH
    Ratings:
    +935 / 0 / -0
    Ugh, that sounds like a PITA.

    I’m clearly no expert, so I’m gonna spitball some off the wall stuff here (and probably be wrong)

    Head to a wreckers and scavange another MAF?

    Alternately, pull out your old trusty Bently Manual, and a multimeter and start checking those pinouts on the ECM? If that checks out, check the loom where it plugs into the MAF. Maybe there’s a bad pin on the connector that can be repaired by attaching a scavenged one?

    It sucks that the ECM is coded per vehicle and you can’t just pull one from another wrecked car and swap it in.
     
  3. DneprDave

    DneprDave Well-Known Member
    Supporting Member

    Oct 23, 2010
    2,861
    1,401
    113
    Engineer
    Pacific NW
    Ratings:
    +1,530 / 0 / -0
    The first thing I'd do is a smoke test and find that vacuum leak.
     
  4. Dave.0

    Dave.0 Helix & RMW Powered
    Lifetime Supporter

    May 4, 2009
    23,950
    13,045
    113
    Burbs of Philly, PA
    Ratings:
    +13,836 / 5 / -4
    Most modern cars with MAF’s will not run without it connected.
     
  5. Sully

    Sully Administrator
    Staff Member Articles Moderator

    Jul 21, 2015
    2,041
    857
    113
    Software
    30350
    Ratings:
    +1,010 / 8 / -0
    Agreed - this whole situation seems crazy. Especially that it will run without the MAF..

    Lets break it down.. car ran prior to doing the work... at that point the MAF worked. You were trying to fix something else.

    Here is where I would start:
    1) pull the MAF and see if the sensor is clean. Note - we would want to do some research on how to clean the sensor if it’s dirty.. that said, I would do it yet. It worked prior.
    2) check all wiring connections for the MAF. Start by ensuring the connector is clean. Then trace the wires back to the firewall. Are the pinched? Anything look worn?
    3) do smoke test for leaks.. which to me is logical... except it runs without the MAF (ie has no reading of air..) so if a leak is there with MAF plugged in should still run.. scratching my head on that.
    4) clean MAF... the reason I put that last is from my experience cleaning a MAF can be tricky. Use the wrong stuff (carb cleaner for example).. and you damage the sensor.

    Can’t believe the shop took the car apart for the MAF... seems very off base.

    Upload pics of what you find. I’ll pull out the trusty Bentley later tonight and see what I can find..

    By chance when you were doing the work on the car, did the MAF fall or take a hit.. ? Is the sensor tight?

    Note - not super familiar with MINIs yet.. so I’m assuming the have a standard MAF confine where the sensor looks something like this... (happened to have my M5 one pulled...)

    image.jpg
     
  6. DneprDave

    DneprDave Well-Known Member
    Supporting Member

    Oct 23, 2010
    2,861
    1,401
    113
    Engineer
    Pacific NW
    Ratings:
    +1,530 / 0 / -0
    On many cars, when the Mass Airflow Sensor is unplugged, the Engine Control Unit will revert to a stored map. It isn't ideal, but it will get you home with reduced performance.
     
  7. Dave.0

    Dave.0 Helix & RMW Powered
    Lifetime Supporter

    May 4, 2009
    23,950
    13,045
    113
    Burbs of Philly, PA
    Ratings:
    +13,836 / 5 / -4
    When ever working on an R56 and above ALWAYS disconnect the battery before unplugging anything.

    Sound like the ECU may need a re-flash. Something is really jacked up with the car.
     
  8. Zapski

    Zapski Well-Known Member

    May 4, 2011
    2,098
    887
    113
    Columbus, OH
    Ratings:
    +935 / 0 / -0
    Having just cleaned my MAF the other day - this is what I used.

    https://www.autozone.com/miscellaneous-cleaners-and-degreasers/electrical-parts-cleaner/crc-mass-air-flow-sensor-cleaner/36011_0_0

    No issues so far from having used it, but it has only been a couple of days. Just read the instructions on the bottle. There are some cars it says not to use it with (Lexus, for example) but MINI wasn’t on the list.
     
  9. ccain

    ccain Active Member
    Supporting Member

    Jan 5, 2013
    152
    56
    28
    Retired
    Ratings:
    +56 / 0 / -0
    Thanks everyone for the advise! I guess I'm just going to have to start digging into it. Here's a video of the main issue I have with the car right now. This is how the dealer released it to me. Like I said, it runs and drives it's just gutless and I forgot to mention that this thing drinks gas like a fighter jet.

     
  10. Dave.0

    Dave.0 Helix & RMW Powered
    Lifetime Supporter

    May 4, 2009
    23,950
    13,045
    113
    Burbs of Philly, PA
    Ratings:
    +13,836 / 5 / -4
    Wow ^^^ that’s sucks. Good luck with that. I would not trust a dealership to look at it again. You need an aftermarket Mini specialist to read the ECU and codes to see what’s going on. You may need a flash and a new or “known good” MAF to test with.
     
  11. Zapski

    Zapski Well-Known Member

    May 4, 2011
    2,098
    887
    113
    Columbus, OH
    Ratings:
    +935 / 0 / -0
    I’m more computer technician than mechanic, and when anything with an electrical connection behaves that way, it’s worth checking the cable that connects the device.

    I’m sticking with my original spitball - Swap in a Known Good MAF first because it’s easiest. Grab one from a local wrecker, no need for full price on a diagnostic part. Also maybe clean the pins on the loom plug with a high percentage isopropyl and an old toothbrush. Allow to dry before reconnecting. Also that product I linked above would work as well.

    If the problem persists, start checking that wiring loom for pinches, bad or loose pins. Get the multimeter out and make sure that whatever wires plug into the MAF actually have conductivity on both ends.

    If the loom checks out, then it’s ECU issues next. I’m concerned that the plugging and unplugging while the system is live and running current could have messed something up. Some electronics don’t care for that sort of thing and get wonky.

    It’s possible that Dave’s right and that a re-flash of the ECU would resolve it, simply because it could have gotten junk data written into a weird memory space that’s presistent if the wrong signal was messed up by unexpected voltage while powered on. In 20 some years of computer repair, I’ve seen weird stuff like that happen (it’s rare but not impossible).

    Finally, that clicking sound from the engine - that only showed up after the weirdness with the MAF?
     
  12. MCS02

    MCS02 Moderator
    Staff Member Articles Moderator Supporting Member

    Jul 31, 2009
    9,562
    5,117
    113
    Male
    Ratings:
    +5,848 / 7 / -0
    I am going to be the loan dissenter. I really really doubt it is an ECU. I even doubt its the MAF, but could be. I say it is a vacuum leak, like DneprDave said. The whistle is the clue. Find what is causing it and I would bet you will find your problem. take a breath and begin at the beginning. There could be a broken hose or a bolt that is not tight. Im starting to think the Mini dealers cant fix anything unless the computer tells them what part to fix. My step dat would call them parts changers, not mechanics. I know your frustrated but I bet when you find it it will be simple not an ECU.
     
  13. MCS02

    MCS02 Moderator
    Staff Member Articles Moderator Supporting Member

    Jul 31, 2009
    9,562
    5,117
    113
    Male
    Ratings:
    +5,848 / 7 / -0
    I just got through telling my buddy the timing on my bike was right only to check it and find it was off. Then I swore I had wired it right. Well after I went over it agin the third time I got it right. Believe me I thought I could not fix it but did.
    Just do some old school trouble shooting first
     
  14. TWA

    TWA New Member

    Jul 28, 2019
    3
    0
    1
    Male
    Ratings:
    +0 / 0 / -0



    I know this post is years old and I hope your still around and remember the problem to your Mini not running when you had the man plugged in. So, do you remember the problem? what was causing the Mini to run better when you unplugged the maf?
     
  15. TWA

    TWA New Member

    Jul 28, 2019
    3
    0
    1
    Male
    Ratings:
    +0 / 0 / -0


    My mini is doing the exact same thing.
     
  16. TWA

    TWA New Member

    Jul 28, 2019
    3
    0
    1
    Male
    Ratings:
    +0 / 0 / -0
     
  17. MCS02

    MCS02 Moderator
    Staff Member Articles Moderator Supporting Member

    Jul 31, 2009
    9,562
    5,117
    113
    Male
    Ratings:
    +5,848 / 7 / -0
    Sorry I am no help. but here's a bump maybe someone can help
     
  18. Sully

    Sully Administrator
    Staff Member Articles Moderator

    Jul 21, 2015
    2,041
    857
    113
    Software
    30350
    Ratings:
    +1,010 / 8 / -0

Share This Page