Results 1 to 4 of 4

Thread: Slight rough idle question-

  1. #1
    Join Date
    Jan 2017
    Location
    orlando,fl
    Posts
    204
    My Cars
    2000 2.3l z3

    Slight rough idle question-

    2000 2.3 automatic trans.
    On occasion- when warming up- I get a rough idle. "feels" like it would be a vacuum leak or timing off. (if it were a 1960's american car)
    Today it did it after running about 1 min. Noticed it as I pulled up to my front gate and put it into park to get out and open the gate.
    After I noticed it---- as an experiment--- I shut it off and restarted the engine. It was completely
    gone when it started back up. Did not re-appear. It has done this 3 or 4 times in the last 3 months.

    I got a schwaben code reader a little while back. I have been checking for codes each time I come home from driving.
    I have gotten lean mixture codes a couple times-
    got a cyl. 6 misfire code 2 days ago.
    (neither of which have reappeared)
    So tonight I thought I would take a scan for codes to see if that rough idle this morning recorded any codes. No engine codes. No tranny codes.
    (dont have the other cable yet to do other modules)

    So im asking myself--- what type of problem would cause rough idle but not generate a code of some kind ?
    Could it be something really basic like the oil is a little dirty and Mr. Vanos is failing to return to home at idle ? (and when I shut it off and
    restarted - that cycled the oil pressure and helped it reset to home ?) Should I try changing the oil a couple times to get it cleaner in there ?
    It has 116K miles--- Ive only owned it about 6 months--(driving it for 2) ---- no idea if the vanos has been updated with the new O-rings-

    The manual with the Schwabben is so large I havnt had time to dig into it yet to understand all it can do...... AND- this is my first scanner too....

    Suggestions ?

    Tim
    Last edited by fairchild; 09-22-2017 at 10:16 PM.

  2. #2
    Join Date
    Oct 2012
    Location
    Louisville, KY
    Posts
    4,503
    My Cars
    1997 BMW Z3 1.9L 5MT
    Quote Originally Posted by fairchild View Post
    2000 2.3 automatic... On occasion- when warming up- I get a rough idle... has done this 3 or 4 times in the last 3 months... got a schwaben code reader... No engine codes... 116K miles--- ... owned it about 6 months...
    Wait until it gets worse and/or there's a code. It's not vanos or oil.
    Last edited by Vintage42; 09-23-2017 at 11:31 AM.
    BMW MOA 696, BMW CCA 1405

  3. #3
    Join Date
    Dec 2007
    Location
    Great Dismal Swamp
    Posts
    16,026
    My Cars
    E36/7 E36/8x2 E46 F25
    That actually is one of the symptoms of a worn VANOS seal on the M52TU/M54 engine. I spent a weekend as a guest of Raj a few years back. Fascinating conversations, one of which was about his old E46 and spending years tracking down a rough cold idle. In a nutshell, after figuring out the issue, he handed the info to BMW. They didn't care; it was an old product at that point. So Beisan Systems was born.


    Anyway, a lean condition can cause your symptoms. The computer is correcting for a mixture issue, and overshoots cold. What code did you have?

    A misfire can also cause your issue. If the computer detects an issue, it will shut down the effected cylinder totally. Restarting the car will reset the system. Again, what code did you have? Code numbers matter. Vague paraphrases of a vague imperfect description that's been through a german-english translation can only get you a vague answer, at best. We need the number.


    /.randy

  4. #4
    Join Date
    Oct 2011
    Location
    Cincinnati, OH
    Posts
    528
    My Cars
    02 Mroady,2007 Z4 coupe
    I would have a slight miss at idle when cold once in a while and then one day a mile from my house I had a coil fail. It was trying to warn me but I didn't listen .

Similar Threads

  1. INPA rough running question... slightly rough idle
    By Cereal in forum 1996 - 2003 (E39)
    Replies: 0
    Last Post: 05-27-2015, 06:33 PM
  2. Slightly rough idle on cold start question
    By kgvickers in forum 1996 - 2003 (E39)
    Replies: 23
    Last Post: 05-29-2008, 01:06 PM
  3. BMW 850i Slight Rough Idling and Hesitation
    By pauldays in forum General BMW Mechanical Help sponsored by RM European Auto Parts
    Replies: 0
    Last Post: 12-08-2004, 11:39 PM
  4. Rough Idle Question
    By BMWFAN in forum 1991 - 1999 (E36)
    Replies: 7
    Last Post: 11-23-2003, 05:11 PM
  5. Slightly rough idle, solutions?
    By Extratx in forum 1992 - 1999 M3 (E36)
    Replies: 5
    Last Post: 02-24-2003, 01:14 PM

Bookmarks

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •