1. Welcome to Tacoma World!

    You are currently viewing as a guest! To get full-access, you need to register for a FREE account.

    As a registered member, you’ll be able to:
    • Participate in all Tacoma discussion topics
    • Communicate privately with other Tacoma owners from around the world
    • Post your own photos in our Members Gallery
    • Access all special features of the site

2.7L engine high idling help!!!

Discussion in 'Technical Chat' started by GrnMchne35, Feb 19, 2012.

  1. Feb 19, 2012 at 10:02 AM
    #1
    GrnMchne35

    GrnMchne35 [OP] Member

    Joined:
    Jan 17, 2012
    Member:
    #70840
    Messages:
    5
    Gender:
    Male
    First Name:
    Jon
    Lancaster, PA
    Vehicle:
    96 Tacoma SX
    6 inch Fabtech suspension lift, 35 inch Dick Cepek mud country tires, performance throttle body spacer,short tube header, 2.7L still kickin strong with 245k miles
    I have a 1996 Tacoma with the 2.7L engine. When I have the truck in neutral the engine stays at a high idle or it fluctuates from a regular RPM to high idle. This happens when its just sitting there idling and as I'm driving and push in the clutch. If anyone knows how to fix this problem please help me out!!!
     
  2. Feb 19, 2012 at 10:05 AM
    #2
    Bishop2Queens6

    Bishop2Queens6 Well-Known Member

    Joined:
    Jun 8, 2011
    Member:
    #57944
    Messages:
    1,317
    Gender:
    Male
    First Name:
    Mike
    SoCal
    Vehicle:
    2009 DCSB MGM
    Afe CAI (removed back to stock intake), TSB 4 leaf pack with Firestone Air Bags and Daystar cradels, 3rd OEM HU, Wranger All Terrain Adventure with Kevlar 265/75/16, Cali raised LED pods, Wheeler Off Road Front Bump Stops.
    Check if there are cracks on the intake tube leading up to the throttle body. My old ford explorer used to do what your truck does; It was from cracks on the intake tube.
     
  3. Feb 20, 2012 at 11:27 AM
    #3
    Dustrider

    Dustrider Well-Known Member

    Joined:
    Nov 23, 2011
    Member:
    #67601
    Messages:
    136
    Gender:
    Male
    First Name:
    Dave
    Hillsboro Oregon
    Vehicle:
    98 Tacoma 4x4 2.7
    First make sure the throttle is closing completly , nothing hanging up the throttle cables or pedal, check that all the vacuum hoses are tight , no obvious vac leaks , a tiny vac leak will raise idle a large leak will cause a stall or stumble

    next check and or clean the idle air control valve (IAC) .
    it is located under the throttle body
    most common cause of idle problems and first thing the mech will check
    the IAC is a drum shaped valve on a magnetic switch that is electrically controlled by 12 volt signals from the computer when engine is cold it switches trough a relay to allow more air intake that raises idle speed, a weak spring keeps it in normal position , the ECT (engine control temp) sensor tells the computer the engine is cold and sends 12 volts to open the IAC , when ECT warms it shuts and the spring takes over
    if the IAC gets sticky it could keep idle up

    to get to it : first remove the air filter cover, unplug Mas air flow ( MAF) sensor then two bolts under the resonator box and remove the entire air intake
    at this point you can try spraying carb cleaner in the TB (throttle body) which should do it
    it probably wont run with the intake off because the MAF sensor in the air filter intake will not get a signal

    another hit and miss way is to just remove the intake at the TB to the side slightly while reving the motor at the throttle and spray Sea Foam brand spray into the intake as it is running to clean it out

    or continue to remove the TB and throughoughly clean
    unbolt the throttle body, pull it up a little to make it easier to get to the plugs and hoses
    unplug the TPS (throttle position sensor) and IAC plug
    then remove the vacuum lines , throttle cables

    removing the IAC from the TB can be difficult because it has phillips screws, a hammer operated impact driver works to get these off
    clean it all out with carb cleaner
    the kweer shaped Oring gasket is very sensitive and should probably be replaced avoid carb cleaner on it
    may also want to replace the TB to intake plenum gasket
    not usually a problem but the IAC an be tested by jumping it to 12v , positive to middle terminal , neg to each other 2 terms
    avoid getting carb cleaner on the TPS
    it is slightly possible that the TPS could be at fault but less likely and a failed TPS would probably leave a check engine light code (CEL)


    report back and let us know what you found so we can learn from it
     
  4. Feb 20, 2012 at 11:50 AM
    #4
    rngrchad

    rngrchad Yankee Oscar Tango Alpha

    Joined:
    Oct 12, 2008
    Member:
    #9919
    Messages:
    183
    Gender:
    Male
    The former USA now USSA (United States Socialst Am
    Vehicle:
    08 Rugged Trail TRD
    Rockwell 30 ton axles.
    Check TPS, check the "coil on plugs" Peace
     
  5. Feb 20, 2012 at 12:20 PM
    #5
    Dustrider

    Dustrider Well-Known Member

    Joined:
    Nov 23, 2011
    Member:
    #67601
    Messages:
    136
    Gender:
    Male
    First Name:
    Dave
    Hillsboro Oregon
    Vehicle:
    98 Tacoma 4x4 2.7
    96 probably has a distributor
     
  6. Feb 21, 2012 at 7:11 AM
    #6
    GrnMchne35

    GrnMchne35 [OP] Member

    Joined:
    Jan 17, 2012
    Member:
    #70840
    Messages:
    5
    Gender:
    Male
    First Name:
    Jon
    Lancaster, PA
    Vehicle:
    96 Tacoma SX
    6 inch Fabtech suspension lift, 35 inch Dick Cepek mud country tires, performance throttle body spacer,short tube header, 2.7L still kickin strong with 245k miles
    Ok Ill try these tips and see if I can fix it, Thanks for the help guys ill keep you posted
     
  7. Feb 21, 2012 at 7:54 AM
    #7
    BlueT

    BlueT Well-Known Member

    Joined:
    Mar 30, 2009
    Member:
    #15341
    Messages:
    5,645
    Gender:
    Male
    NorthEast
    Vehicle:
    07 Dbl Cab LB with LSD
    I moded 1999 Taco so much it had turned to Land Cruiser
    x2...
    OP check IAC and clean TB also check ETC if it is not fried. Check resistance of ETC and resistance against ETC body. If resistance in ETC is less then 10 ohms against body you need new ETC. FSM has checks but they dont have one for ETC body. They just tell you to check internal ETC resistance.
     
To Top