Focus surging

Discussion in 'Domestics' started by GMC guy, Jul 11, 2017.

  1. GMC guy

    GMC guy Hero Member

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    Please fill out the following to ask a question.

    Ford
    Focus
    2003
    170 km

    2003 focus surges when going down the street. It used to do this slightly and only on a specific road. Now it's doing it all the time. Thanks in advance
     
  2. billr

    billr wrench Staff Member

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    No codes set? Do you have live-data? If no other info is available, I would check fuel pressure (with a gauge!) and try blocking off the EGR valve, if it has one. Also, inspect all vacuum hoses, especially the ones for PCV and brake boost, for cracks that could be opening up and causing an intermittent vacuum leak.
     
  3. Mobile Dan

    Mobile Dan wrench

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    Maybe need to clean your Mass Airflow Sensor.
     
  4. nickb2

    nickb2 Wrench. I help when I can

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    Hmm, yeah need more info. No mention of what engine. There were 4 made for this year car. Vin numbers 3, 5, P, Z. Three with 2.0l's, two of which are DOHC, the other SOHC, the last one is a 2.3l, All are 4 naggers obviously.

    Surging while driving is quite different then at idle. I would certainly check for air intake duct cracks. Surely will cause surging under load/driving and will usually settle down at idle as the crack folds into itself. Easy enough check to do. Just flex the intake air duck back and forth while at idle and notice idle changes or downright stalling.

    And, as stated above in previous post, is live data available to you, if so, you can certainly post if there are any codes and post the fuel trims while it surges.
     

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