Question on the air flow measuring unit on my Elantra..

Discussion in 'Hyundai Elantra / Lantra' started by Vector Viper, Jan 11, 2005.

  1. Vector Viper

    Vector Viper Guest

    It is a 1992 Elantra, early production. I have been fighting low
    power at low RPMs and a pulsing/bouncing idle, also, the idle
    speed
    seems to vary alot after it has been driven awhile. I checked the
    output from the air-flow sensor, and found it REALLY jumpy at
    idle,
    how smooth is it supposed to be? The computer was replaced (the
    old MITS one crapped out) The car just drives weird with low
    power...
    Are there any mods to make on this car to improve it to the later
    1992 ones?

    Thanks for any info as always,
    AJH
     
    Vector Viper, Jan 11, 2005
    #1
  2. Vector Viper

    hyundaitech Guest

    There are no siginificant differences between the early 92 and later 92
    vehicles. In fact, I don't recall any, but I'm sure there are probably a
    couple.

    The bouncing idle is caused by too much air entering the engine. The
    computer begins shutting off the injectors in an effort to slow the engine
    down. As the injector pulse starts/stops, the engine revs up and down,
    causing the bouncing. I've seen improper repairs where the throttle was
    pulled open by adjusting the throttle cable on cars which were stalling.
    This will cause the bouncing condition you describe. Check your throttle
    cable to be sure it isn't holding the throttle plate open. Check the air
    bypass screw to be sure it isn't allowing too much air into the engine.
    Check your idle actuator. It screws into the bottom of the throttle body
    and has a six pin connector with two rows of three pins. If I recall
    correctly, the resistance in each row between the center pin and each of
    the outer pins should be about 30-35 Ohms. If the actuator doesn't work
    properly, it could cause the bouncing idle. If it's shorted, it WILL blow
    up the computer. An open circuit just won't work, but won't kill the
    computer.

    The air flow readings are jumpy at idle because your car isn't idling
    steady. The air flow readings should be steady, but so should your rpm's.
    Address the rpm's first and the air flow readings should follow.

    Low power typically has nothing to do with idle settings. Can you tell if
    the car's misfiring? Low rpm lack of power issues tend to be caused by
    ignition misfires. If you're misfiring, I'd check the plugs, wires, and
    coil. Does it matter whether the car is cold or hot in terms of the lack
    of power? Does it matter how fast you're going?
     
    hyundaitech, Jan 11, 2005
    #2
Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.