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Variable Assist Power Steering

Discussion in 'Technical Chat' started by Waverly, Oct 20, 2011.

  1. Oct 20, 2011 at 7:24 AM
    #1
    Waverly

    Waverly [OP] Well-Known Member

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    Finally got to the bottom about what is going on with the tight steering on my truck.
    Took it back to the dealer....again...about the issues with tighter steering at highway speeds. One of the service managers out of the three....told me that these trucks have the variable assist power steering. While driving in town driving...lower speeds...the steering is...ah....soft...what you think power steering should be. When your out on the highway at highway speeds....it gets tighter as you will not apt to over steer and lose control. It's control electronically with the steering rack....
    I checked it out on other sites on the net to verify.
    So truck is doing what it's suppose to be doing......
     
  2. Dec 16, 2011 at 4:42 PM
    #2
    rzimm001

    rzimm001 Tearmytaco

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    King 10" coilovers w/ resi. 3.5" over long travel kit. Factory spindles w/ ALLPRO gussets. Total Chaos tower gussets. Energy Poly cab mounts and steering rack mounts. Glassworks fenders and bedsides. Home fabbed bed cage. King 2.5x16 bypass shocks in the rear. DMZ long travel rear end. Race radio (2meter). Removed secondary carbon air filter. Exhaust dumped before the axle / no muffler. Phram fresh air cabin filter. K&N replacement filter, After market stereo, Grillcraft grill, custom fabled roof rack with 7" HID's, PRP race seats.
    ?? You sure? I had to replace my steering rack myself just recently. Grenaded it offroading... long story. However, no electrical wires were going down to the steering rack when I replaced it. How does this function you speak of work?
     
  3. Dec 16, 2011 at 4:44 PM
    #3
    chris4x4

    chris4x4 With sufficient thrust, pigs fly just fine. Moderator

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    4.10 gears, sliders, and lots of buttons.
    Yeah....I havent heard of the variable assit on the Tacoma. Sounds like they are talking out their ass again.
     
  4. Dec 17, 2011 at 5:54 AM
    #4
    BUZZCUT

    BUZZCUT Well-Known Member

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    My son's 97 GMC has it. It is an electric valve on the power steering pump and it opens and closes depending on the input from the steering wheel. Lower speeds=more assist higher speeds=less assist. On the GMC it has a sensor on the bottom of the steering column that senses the rotation and send the signal to the valve.

    Not sure if this is the case for the later model yaks a wiring diagrams could help confirm this.
     
  5. Dec 23, 2011 at 8:57 PM
    #5
    rzimm001

    rzimm001 Tearmytaco

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    I see the electrical connection going to the pump like you are talking about. My power steering has been a lot tighter than normal lately (replaced the rack six months back from an offroading accident). It was fine after the rack replacement, for about at least two months. Now I experience the tighter steering at higher and lower speeds just driving around town. Just to try something I unplugged the connection going to the pump. No difference....

    Does that mean the variable assist isn't working in the first place like it should. I'm trying to troubleshoot my tight steering but don't know what else to try.

    Things I've tried:
    Tire pressure
    New serpentine belt
    Alignment

    What I know:
    No leaking fluid
    Reservoir fluid appears clean (replaced when rack was installed)
    Tightness is consistant and doesn't vary with weather or direction
     
  6. Dec 23, 2011 at 9:24 PM
    #6
    chris4x4

    chris4x4 With sufficient thrust, pigs fly just fine. Moderator

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    4.10 gears, sliders, and lots of buttons.
    These elestrical conectors you guys are looking at, go to the ECU and the engine idels up higher when you turn the wheel at low speeds, to prevent stalling.
     
  7. Dec 24, 2011 at 1:29 PM
    #7
    BUZZCUT

    BUZZCUT Well-Known Member

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    Makes Sense.
     
  8. Feb 10, 2012 at 9:28 PM
    #8
    Waverly

    Waverly [OP] Well-Known Member

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    The guy told me he thought 2010 was the 1st year for the variable assist power steering.....not unless they are lying to me...
     
  9. Feb 10, 2012 at 9:36 PM
    #9
    Waverly

    Waverly [OP] Well-Known Member

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  10. Feb 10, 2012 at 9:41 PM
    #10
    chris4x4

    chris4x4 With sufficient thrust, pigs fly just fine. Moderator

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    4.10 gears, sliders, and lots of buttons.
    It is "Variable assist", but not with an electric motor. At low speeds, more assist is given, then it reduces at higher speeds. THe power steering pump still supplies the power, and controls how much.
     
  11. Feb 10, 2012 at 9:42 PM
    #11
    chris4x4

    chris4x4 With sufficient thrust, pigs fly just fine. Moderator

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    4.10 gears, sliders, and lots of buttons.
    I was thinking of an assist by electric motor when I typed this.
     
  12. Feb 10, 2012 at 9:47 PM
    #12
    Waverly

    Waverly [OP] Well-Known Member

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    Ok Chris...
    these are spec for the 2012...but I also google and found the specs on the 2010 and it had the variable assist also.
    I am not sure I like it either......What year is your Tacoma and does it have it also??
    Thanks
     
  13. Feb 10, 2012 at 10:11 PM
    #13
    chris4x4

    chris4x4 With sufficient thrust, pigs fly just fine. Moderator

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    4.10 gears, sliders, and lots of buttons.
    Mines an 07. IIRc, it was on all the Tacomas from 2000 on up.
     
  14. Feb 11, 2012 at 5:40 PM
    #14
    GWH

    GWH Member

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    I am having the same problem and was wondering if changing the power steering pump would fix the problem?
     
  15. Feb 11, 2012 at 7:35 PM
    #15
    Waverly

    Waverly [OP] Well-Known Member

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    They changed the (vein pump) power steering pump on mine before they told me it was the variable assist power steering....:rolleyes:
    Did not make a lot of difference.....
    My boy has a 2007 tacoma...equipped exactly like mine...and the steering feels the same..
     
  16. Feb 12, 2012 at 5:44 PM
    #16
    GWH

    GWH Member

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    So is there something I can do or do I need to take it in and have it looked at?
     
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