Fast Idle Thermo Valve

Discussion in 'General Motoring' started by Rubntugdug, May 12, 2008.

  1. Rubntugdug

    Rubntugdug Guest

    I've been driving an automatic 1990 Honda Civic DX for 2 and a half years.
    The Car has been great, but always idles really high before it is warmed up.
    Especially if not used for a couple of days.
    I realized that it will idle higher than normal when cold, but this is
    really high, and I have to keep my foot on the brake pedal or it will take
    off on me until warmed up.
    Through reading forums and and other internet sources I have reason to
    believe it may be the Fast Idle Thermo Valve. I realize there are other
    possibilities!
    I have seen a write up on other forums with pictures, and they show how to
    screw in some kind of plunger in said FITV.
    The problem is that the pictures show an Integra engine bay, not a Honda
    Civic.
    Apparently the FITV loosens up over time.
    I have the Haynes manual, and have looked under the hood for the FITV, but
    cannot find the damn thing!
    I am not a mechanic, and have only done basics like 02 sensor, Cap, rotor,
    ignition coil and spark plugs, etc.
    Does anyone have a link with a picture, or a diagram or description for this
    year(1990) Honda Civic in regards to the FITV?
    Thanks.
     
    Rubntugdug, May 12, 2008
    #1
  2. Rubntugdug

    jim beam Guest

    presumably an automatic.

    any idea what the revs are? [you can buy an instrument cluster from a
    junkyard, with tach, for about $40 these days.]

    higher revs are normal - ~1500. and at that speed, the torque converter
    will pull quite strongly. are your brakes good?

    that's 99% of your problem right there.

    first stop is tegger.com for the faq's and links to factory workshop
    manual downloads.

    next step is check all your hose connections, then test fast idle and
    iac valve operation per the manual.
     
    jim beam, May 12, 2008
    #2
  3. Rubntugdug

    Rubntugdug Guest

    Thanks for the reply.
    Can anyone tell me where FITV is in the engine bay?
    I've looked around the intake manifold but cannot see it??!
     
    Rubntugdug, May 12, 2008
    #3
  4. Rubntugdug

    bi241 Guest

    Unless the idle speed will not come back down after warm up, then i'd
    suggest you leave the FITV as is, it serves a purpose.

    When engine temp is cold, the valve opens to allow more air to enter
    the intake manifold (behind the throttle plate) to increase idle speed
    and reduces warm-up time. It utilises a form of controlled vacumm
    leak, similar to that of the PCV valve

    And also by allowing more air to enter, it helps offset the harmful
    effects of the rich mixture caused by the IAT sensor during the warm
    up period.

    Now you just want to drive right away, of cource you can shut the damn
    valve closed permanently by doing such modification so that the
    transmission and the brakes are not subjected to too much unnecessary
    stresses.

    But why would you want to put your engine under load, any load, when
    it's still cold?

    The warm-up period is the nastiest condition that an internal
    combustion engine has to endure. Uneven distribution of lubricant,
    concentration of heat, wet mixture, low fuel burning efficiency, off
    valve timing... blah blah... and God created the FITV
     
    bi241, May 13, 2008
    #4
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