Weird Idle Surging

Discussion in '96-04 - 2V Specific' started by Carnage281, May 7, 2015.

  1. Carnage281

    Carnage281 Active Member

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    So I just got my longtubes installed and loaded up my 93 octane tune on my x4. It had been idle surging a little after I loaded my tune, but I thought it might have been the vac leak I had on my pcv hose. So I got that fixed and it stopped for a few days and now it's back. It's a little odd tho, every time I start it the rpms surge from 1,000 to 500 every few seconds then drop to 300 and occasionally stall the car out. However, when I rev the car a few times or drive around a bit it will idle fine until the next time I start it. So what do you guys think it is? I have read a few threads on other forums that have addressed surging but I haven't seen one that stops after being driven or revved. Could this be related to my tune?
     
  2. lwarrior1016

    lwarrior1016 Moderator Staff SN95 Supporter

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    Who did your long tube install? Did you make sure there are no exhaust leaks at the gaskets? I know an upstream exhaust leak will act like a vacuum leak and cause all sorts of weird things to happen. Then, have you tried loading a different tune in it to see if it made a difference.