Acura CSX rear stepping out on bumps.

Discussion in 'The Garage' started by MotorradMike, Apr 18, 2013.

  1. MotorradMike

    MotorradMike MIL-TFD-41

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    Hi guys:

    I just bought a 2009 CSX and am liking it a lot.
    Only problem is that the rear end shudders and steps out a bit even on a straight.
    I've cornered pretty hard but haven't hit a significant bump so don't know if it'll go nuts when that happens.

    I pulled the lower shock bolts and the shocks are smooth and damp fine.
    The only alignment parameter on the rear is camber.
    Tire pressures are all 33PSI as required.

    I'm going to try reducing rear tire pressure but am hoping some of you guys have other suggestions.
    #1
  2. Hastelloy-X

    Hastelloy-X Been here awhile

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    My father's Dodge Stratus did this too.

    He took it in to a spring and alignment shop and they found a bent suspension piece on the rear suspension.

    They told him they see it alot; that it can happen if you cut a corner and hit a curb for example.
    #2
  3. LuciferMutt

    LuciferMutt Rides slow bike slow

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    You can't tell if a car shock is good by cycling it by hand.


    Rear step-outs are almost always related to bad toe-in/out settings on the rear wheel. I know you said the only alignment parameter is camber, but I'd be surprised if there isn't a way for a shop to set toe-in, possibly through use of shims/washers, whatever. If the rear is getting really jittery, I suspect there is toe-out where there isn't supposed to be any.
    #3
  4. victor441

    victor441 Long timer

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    You could get some conduit, string, etc. and check the basic alignment out yourself (even if you don't want to fix it yourself)....if something is seriously out it should be evident. I used the method below recently with good results and very low $$$...with a newer more valuable car like yours I'd probably let a pro do any repairs/adjustments if needed but checking out the basics is fairly easy.

    http://www.hotrod.com/techarticles/chassis/hrdp_0411_wheel_alignment_guide/viewall.html
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  5. mnsty

    mnsty Been here awhile

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    Static toe is one thing, bump steer is another. It's toe in or out as the suspension cycles through its range of motion. Sounds like that's what is happening.
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  6. LuciferMutt

    LuciferMutt Rides slow bike slow

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    Excellent point; I totally forgot to mention this! If some bushings are worn out, the suspension may be introducing toe to the tire as the suspension compresses.
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  7. MotorradMike

    MotorradMike MIL-TFD-41

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    Hmmm, every bad shock I've changed was obviously screwed up, are you saying the only way to find out is to put new ones in?
    I tried bouncing the bumper but the suspension is really stiff and there's no real bumper to bounce on so that method didn't get me anywhere.

    Thanks for that link, I'm going to try the string/conduit thing.


    I knew you guys would give me some things to check.
    Thanks to all.
    The Acura sites I've found seem to be more geared towards cosmetic stuff.
    #7
  8. concours

    concours WFO for 41 years

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    How mnay miles on the shocks? Tires?
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  9. MotorradMike

    MotorradMike MIL-TFD-41

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    Tires are new and balanced perfectly. On smooth pavement there is no hint of any shaking or pulling or anything up to 85 MPH.
    The shocks are very likely original with 42,000 miles.
    The ride is very firm so bumps are all felt.

    The rear just steps out slightly over a bump at speed.
    Maybe it's normal, but what do I know.
    I'm going to check the alignment with the string/conduit trick because if I go back to the dealer without some kind of evidence I'm sure they'll just say it's normal.
    The only shop guy around here I trust doesn't have alignment equipment.

    Things have ramped up here so I won't get to it for a bit.

    Thanks for your input, I'll keep you posted.
    #9
  10. victor441

    victor441 Long timer

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    Good luck, hope nothing is seriously tweaked and/or difficult to repair. Since you are checking the alignment yourself it is also easy to get a general idea on camber if the car is leveled up per the hotrod article....if you hold a carpenters level vertically near the wheel and measure the distance from the top and bottom of the rim to the level with a little trig you can get the camber... i.e. on a 15" wheel a 1/4" (or 6mm) difference is about 1 degree of camber. BTW, while checking my car out recently I eventually figured out it was MUCH less confusing to use a metric ruler and tape measure to check out camber and toe in.....for a basic check 1 mm (1/25 inch) accuracy worked for me.

    [​IMG]
    #10
  11. RocketJohn

    RocketJohn Hook em' Horns!

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  12. Dave in Wi

    Dave in Wi Long timer

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    On the last 2 Japanese sedans I owned, the rear tire pressure recommendation was 2 or 3 psi less than the front. Overinflation could lead to oversteer in hard cornering (as my wife found out on an off ramp once). Even so this shouldn't cause the rear to step out on straght roads.
    #12