Results 1 to 11 of 11

Thread: Start up stumble

  1. #1
    Join Date
    Sep 2005
    Location
    Peoria, AZ
    Posts
    7,696
    My Cars
    03 zhp, 97 e36m3, 04 zhp

    Start up stumble

    2004 330i, 152K miles: Most of the time, but not always, when I start the car it would stumble for a couple of seconds with virtually no throttle response until it evens itself out or throttle gains its sensitivity and actually revs up the engine a bit. Car has no codes, fuel filter looks recent. The car does this regardless of the engine temp, it could be fully warmed up or stone cold. Holding the key in the second position for a few seconds (fuel priming) does not help the issue. Fuel pressure at the rail looks right during priming and while running. Car runs good otherwise with good power and no codes, stable RPM while idling cold or warm, no vanos noises or any other abnormal noises for that matter. Battery checked out ok, spark plugs look normal. Any further ideas on the root cause? I got the fuel pump here, but I have a strong feeling it isn't fuel related - don't want to just start throwing parts at the problem. Am I missing something obvious?

    Thanks.

  2. #2
    Join Date
    Feb 2012
    Posts
    20
    Hi mate it could probably be the breather pipes they start to perish because they are poxy plastic i would start checking them easiest way is to replace all of the and the breath pipe filter you can usually get it as a full kit i think there is 5 pipes an a filter but they dont come cheap an take some advice dont buy cheap ones because you will end up spending out on dear ones any way so go dear first hope this helps

    Sent from my SM-G920F using Tapatalk

  3. #3
    Join Date
    Jan 2009
    Location
    Chicago, IL
    Posts
    431
    My Cars
    2001 330i and 2005 330i
    turn the key to position 2 (dash lights buy no start) for 30 seconds, then turn it off for 10 seconds. Then start the car. Could be an adaption fault and the key thing helps reset that. Otherwise you'll need a spare laptop, cable, and software to do more. (See the diagnostic section of the forum.)
    Johnny Murray

  4. #4
    Join Date
    Sep 2005
    Location
    Peoria, AZ
    Posts
    7,696
    My Cars
    03 zhp, 97 e36m3, 04 zhp
    Quote Originally Posted by johnjmurray View Post
    turn the key to position 2 (dash lights buy no start) for 30 seconds, then turn it off for 10 seconds. Then start the car. Could be an adaption fault and the key thing helps reset that. Otherwise you'll need a spare laptop, cable, and software to do more. (See the diagnostic section of the forum.)
    Thanks, I'll give this a shot.

    Leaning towards replacing the pump since they all go sooner than later anyway.

  5. #5
    Join Date
    Mar 2017
    Location
    Norwich, Connecticut.
    Posts
    486
    My Cars
    E46 wag. E36 convertible
    Not trying to be a prick.....But how many BMW mechanics, shaddy tree, or waht...actually respond to the people asking valid questions on here....bimmerfest?

  6. #6
    Join Date
    Aug 2014
    Location
    Lawrence Kansas
    Posts
    1,236
    My Cars
    2004 325XI/2008 GL320
    When you say no codes, are there any shadow codes?

  7. #7
    Join Date
    Sep 2005
    Location
    Peoria, AZ
    Posts
    7,696
    My Cars
    03 zhp, 97 e36m3, 04 zhp
    Quote Originally Posted by dhurley34 View Post
    When you say no codes, are there any shadow codes?
    Good questions. I know there were errors of some sort, I'd need to run a scan again. Totally dismissed those somehow. Will post back. Thanks.

  8. #8
    Join Date
    Feb 2013
    Location
    California
    Posts
    202
    My Cars
    '06 zhp coupe
    I bet you'll find misfire codes. It's very common with the M54B30

  9. #9
    Join Date
    Aug 2014
    Location
    Lawrence Kansas
    Posts
    1,236
    My Cars
    2004 325XI/2008 GL320
    Quote Originally Posted by Mless5 View Post
    Good questions. I know there were errors of some sort, I'd need to run a scan again. Totally dismissed those somehow. Will post back. Thanks.
    Short misfires during cold start up will not trigger a CEL, but will store the code as a shadow with the offending cylinder number. If you have not done so, clean the idle air control valve.

  10. #10
    Join Date
    Sep 2005
    Location
    Peoria, AZ
    Posts
    7,696
    My Cars
    03 zhp, 97 e36m3, 04 zhp
    No shadow codes were present. I swapped a fuel filter thinking it may be the culprit, but the original one ended up being only 2 years old, Kayser was the brand - no change after fuel filter swap obviously. I have checked injectors and none of the leaked. Decided to bite the bullet and swap the fuel pump and whatdoyaknow - car now starts without any stumbles or hesitation.

    Thanks for your help!

  11. #11
    Join Date
    Sep 2005
    Location
    Peoria, AZ
    Posts
    7,696
    My Cars
    03 zhp, 97 e36m3, 04 zhp
    Spoke too soon I guess. It definitely starts better, but the stumble is still there. My wife reported lack of throttle response followed by a jerk forward on the first application of throttle after start up. Thinking it could be a sticking flap in the throttle body?

Similar Threads

  1. Help! can't figure out engine stumble on cold start up
    By JberazaE36 in forum 1991 - 1999 (E36)
    Replies: 2
    Last Post: 04-08-2014, 05:50 AM
  2. stumble on start up
    By rooster in forum 1991 - 1999 (E36)
    Replies: 1
    Last Post: 08-23-2009, 07:35 PM
  3. Stumbles on Start Up
    By RMStephenson in forum 1992 - 1999 M3 (E36)
    Replies: 5
    Last Post: 12-05-2006, 07:44 PM
  4. Can anyone start up a LTW Pulley Group buy....i would do it but no connections.
    By M3Jokster in forum General BMW and Automotive Discussion sponsored by Intercity Lines
    Replies: 1
    Last Post: 10-09-2001, 02:21 AM
  5. does Jim C. chip make car start up take longer?
    By ///M3 4-LIFE in forum 1992 - 1999 M3 (E36)
    Replies: 2
    Last Post: 09-22-2001, 07:34 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
  •