1st Gen R53 Cooper S Most liked posts in thread: Rough Idling @ Cold Start & Random Misfire Issues

  1. grodenglaive

    grodenglaive New Member

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    #2 grodenglaive, May 1, 2012
    Wow, that's low mileage for an '02. First off, I'd throw in a can of redline fuel system cleaner and give it the italian tune up. See if that helps, it often does.
     
  2. Crashton

    Crashton Club Coordinator

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    #7 Crashton, May 1, 2012
    I've had very good luck with Techron over the years.
     
  3. k-huevo

    k-huevo Club Coordinator

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    #8 k-huevo, May 1, 2012
    I use and recommend FP60.

    First replace the spark plug wires with new OEM, and provide an update afterward.
     
  4. k-huevo

    k-huevo Club Coordinator

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    #10 k-huevo, May 1, 2012
    I experience this each year around this time when summer blends are introduced. You're using ethanol free fuel so this shouldn't apply.

    If you're not sure the ECU has the latest MINI program installed, I would look into an update.
     
  5. minsanity

    minsanity Well-Known Member

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    #13 minsanity, May 1, 2012
    A quick update. Tried an old set of plug wires which definitely smoothed out the idle of the cold engine by @ least 70%. Upon 1st start up of the day, rpm was a bit rough for less than a minute but didn't stumble below 1k til it got warmer. Idle settled @ around +/- 750 upon reaching operating temp.
    Guess It's off to new wires & plugs + a fill up w/ injector cleaner/booster.
    Again, I'll still do this by elimination & see.
    Thanks for all your spot on ideas & help. Hoping to get this back healthy!
     
  6. Jason Montague

    Jason Montague New Member
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    #3 Jason Montague, May 1, 2012
    :cornut: P0300 = random/multiple cylinder misfire. Most likely: 1.plugs 2.ignition wires 3.coil 4.cylinder/valve carbon build up.
    Advice above is good advice. I would say: 1. change plugs 2. redline or SEAFOAM in the gas tank and through the intake(see our MA threads on Seafoam) at operating temp followed by Italian(spirited 30min highway acceleration and sustained speed) tune up.:Thumbsup:

    Jason
     
  7. k-huevo

    k-huevo Club Coordinator

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    #4 k-huevo, May 1, 2012
    Because of the low mileage over a ten year period, I'm sure there is moisture accumulation in the fuel tank, and this could be part of the problem. Fueling after or during a station's storage fill could produce similar symptoms. Regardless, the first thing I would do is replace the spark plug wires with new OEM.

    A DSC code is a separate issue probably not connected to misfires.

    If you're not seeing a P1688, battery lamp, or overheating, then probably not the crankshaft vibration damper or belt. Idle is seldom affected with those failures. Although, if the belt has never been replaced I would change it due to possible oxidation, and try wiggling the damper while you're at it.
     
  8. minsanity

    minsanity Well-Known Member

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    #5 minsanity, May 1, 2012
    Thanks for your replies, guys! I definitely welcome & would try all sound suggestions by elimination. Keep em comin'. Anyone tried similar symptoms? Kinda annoying at start up. Strange thing is cold start up turns engine instanly but gets a minute of rough idling, while when warm, engine turns after a bit of longer cranking but idles well. Hmmm. :confused5: Thought my coolant temp sensor was shot, hence the replacement. Off to trying advices....Thanks!
     
  9. minsanity

    minsanity Well-Known Member

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    #6 minsanity, May 1, 2012
    Thanks for chiming right in K-huevo. Really admire the work you do! :Thumbsup:

    When Belt was replaced a coupla days ago, it still looked good, though thinner, of course. Have'nt seen 1688 & tried wiggling & turning the damper. Seemed good w/ no visible cracks. No overheating. Is PRW as good as ATI?

    1 habit of mine is to fill up when it isn't too hot out to get denser fuel. Dunno if that compunds more moisture into the tank. Would consuming this tank to maybe 1/4 level & refiiling from a different station be a logical approach? I'll definitely replace plugs. DSC lights up more often than SES when engine stumbles, but not everytime. Toggle can't switch it off. It turns off after every engine restart restart though. Any ideas on longer cranking issue when engine's warm?

    Aside from Seafoam & Redline, what other cleaner/booster brands would you recommend?

    Apologies for such a long post. Hoping to be enlightened. Thanks tons!
     
  10. BlimeyCabrio

    BlimeyCabrio Oscar Goldman of MINIs
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    #9 BlimeyCabrio, May 1, 2012
    Ditto Keith's spark plug wires recommendation. Numerous times over the past 112k miles, I've had weird misfire issues. It almost always comes down to wires or corroded terminals in my cases.
     
  11. minsanity

    minsanity Well-Known Member

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    #11 minsanity, May 1, 2012
    Will definitely heed your advices,guys! We'll see what works & will keep you posted. Never had to woory about lil quirks with my other cars (toyotas). But this 1 I love the most. Really appreciate y'all for helping out!
     
  12. Newbs49

    Newbs49 New Member

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    #12 Newbs49, May 1, 2012
    TECHRON
    The best there is!!!!!!!!!!!
     
  13. Austinsynthetics

    Austinsynthetics Active Member
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    #14 Austinsynthetics, May 2, 2012
    Other cleaners....

    Amsoil's Performance Improver works well too, see specifics using the attached link. MA members get 15% off displayed price using code MA201201 upon checkout from the site. P.i. Performance Improver Gasoline Additive - Austin Synthetics
     
  14. minsanity

    minsanity Well-Known Member

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    #15 minsanity, May 3, 2012
    Update:
    1. A freah tank of vPower seemed to eliminate warm engine start issues. A bad case of bad gas, I guess.
    2. Cold engine rough idle still came up, quickly turned off engine, cleaned old plug/wire terminals w/ some dielectric contact cleaner by wd40. Restarted engine. Whoa, SMOOTH! I'll have to stock em, wires & plugs then.

    Thanks y'all! I never doubted M/A, dint even post these issues elsewhere. A huge :Thumbsup: guys!
     
  15. turboguy327

    turboguy327 New Member

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    #16 turboguy327, May 3, 2012
    Just a tip. The refueling when its not hot out isn't true at all. Fill up a gas can on a hot day and feel the temp of the gas. Its cold because the tanks are buried a few feet underground. Always the same temp. I ride a bike and can feel the ice cold fuel inside the tank on a hot day when I fuel up.