problem with revs

  1. Infrequent Poster Joined: Jan 2011 Southampton / Bucks Posts: 107 black saxo vts mk2 + white mk3 fiesta
    #1
    hi, i have a problem with my vts.

    when first starting it and pulling away, as i give it some gas the revs seem to drop down and there is a major loss of power. if i come off the gas or you into neutral and rev it up a bit it goes but then may do it again.

    after the engine has warmed up it seems to sort its self out, sometimes after driving for a bit then stoping at traffic lights, going into neutral the revs will drop down and will almost stall.

    could this be a sensor or something on the throttle body thats carbed up? or maybe a choke prob?

    any help would be much appreciated.

    many thanks adam.
  2. Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.
    #2
    Lambda sensor or coil pack on their way out,or just needs a good service.
  3. Infrequent Poster Joined: Mar 2012 Suffolk Posts: 146 SAXO VTR (2001) FIESTA S (2004)
    #3
    worth checking the connection to the coolant temp sensor, know it sounds stupid but its worth a look, give it a wiggle and see if it affects it, happened a couple of times to me
  4. Saxperience Hardcore! Joined: Dec 2007 smurfland. Posts: 17346 Ex saxo owner.
    #4
    Or you`re not letting the car warm up properly mate.
  5. Saxperience Post Whore Joined: Nov 2010 Kent Posts: 8439 Gen 7 Celica 190.
    #5
    Quote:
    Originally Posted by stevo67 View Post
    Or you`re not letting the car warm up properly mate.
    That would not make it bog down and loose power, camshafts wont like it though
  6. Frequent Poster Joined: Aug 2011 nr bognor regis ,west sussex Posts: 787 saxo 16v JP4
    #6
    this is exactly the same problem with mine, amongst other things, I have changed coil pack, spark plugs, lambda and run some redex injector cleaner through it and still same issue. When sat at lights it kinda hunts for a bit between 500 and 1k revs and then dies or saves itself and does it again? also when on the gas feels laggy at points?
  7. Infrequent Poster Joined: Mar 2012 Suffolk Posts: 146 SAXO VTR (2001) FIESTA S (2004)
    #7
    Quote:
    Originally Posted by SaxoVTRben View Post
    this is exactly the same problem with mine, amongst other things, I have changed coil pack, spark plugs, lambda and run some redex injector cleaner through it and still same issue. When sat at lights it kinda hunts for a bit between 500 and 1k revs and then dies or saves itself and does it again? also when on the gas feels laggy at points?
    This really does sound the same as what mine did with the sensor, it was the aftermarket air filter rubbing on the connection block, it kept dropping down and then revving high then going down again, basically revving itself. I still cant believe it was just a wire, i could have sworn it was completely shagged!
  8. Frequent Poster Joined: Dec 2010 Mid Wales Posts: 604 03 vtr
    #8
    have a similar issue on my 1.1 spi. Have changed the coolant and air temp sensors, full service, stepper motor, ht leads, crank sensor but still nothing, got some injector cleaner. I even did my valve clearances! Also got it through an mot so surely the lambda sensors ok. Nothing on diagnostics either. So my advice is to try and sweet talk another vts in your area to let u borrow their sensors one at a time! Oh and if anyone has any ideas of what i should try next i am all ears!