2000 Dodge Neon shakes while stopped and in gear

Discussion in 'The Garage' started by murphy55d, Jul 20, 2009.

  1. murphy55d

    murphy55d Lifer

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    Cliffs:

    2000 Dodge Neon
    Shakes considerably while stopped, but in drive (ie red lights, stop signs, etc)
    Does not shake while in gear and actually moving
    Usually happens after car has heated up to normal temp
    Park/Neutral minimizes the shaking
    AC seems to make it worse but that could be my imagination

    I know that isn't a whole lot to go by, and i've googled a little, but haven't found anything solid. Before I take it to a mechanic and have to pay for diagnostics, anyone ever come across this?

    some things I found when googling, included fuel filter, spark plugs, and Air intake sensors. Anything else I can do myself or check on before I take it somewhere?
     
  2. RGUN

    RGUN Golden Member

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    Clean your idle air control valve. The car is shaking because the rpm's have dropped too low. Putting it in park/neutral helps by taking load off, running ac hurts because of added load. The air bypass that allows you to idle with a closed throttle is restricting the air too much (because of built up crap) and causing it to drop revs. So it should either require a cleaning or the IAC motor is dying.
     
  3. angry hampster

    angry hampster Diamond Member

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    Could also be a harmonic balancer getting loose.
     
  4. cprince

    cprince Senior member

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    does the car shake more when you depress the brake pedal? If so, it could be the brake booster going bad.
     
  5. radioouman

    radioouman Diamond Member

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    Vacuum leak
     
  6. boomerang

    boomerang Lifer

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    There is a switch on the shifter that tells the computer when the car is in a drive gear. The computer uses that information to know how to control the idle speed. This switch could be bad.

    But ...... you say it's still shaking (although less) even in Park or Neutral, so the other ideas you've gotten so far could be in play also and are probably more likely culprits.

    As far as what you can do yourself, we don't what your capabilities are. You don't say your mileage, but if it's due for plugs (and wires), you could certainly do that yourself. Air filter of course is an easy task. Don't replace sensors in hopes of correcting a problem. Replace a sensor only when you know it's bad. Anyone can throw parts at a problem in hopes of fixing it.
     
  7. Arkaign

    Arkaign Lifer

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    Hey, I found the problem :)

    lol j/k, fwiw I shared the misery of owning one of those for a time. The above suggestions for a fix are very sound.
     
  8. murphy55d

    murphy55d Lifer

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    Oh, mileage is 91k. Sorry.

    I bought some fuel system cleaner at Advance and the guy said it sounded like plugs to him. Just throwing that out there.

    My capabilities are not much. I don't really know how to do anything, honestly. Is there anything that a car dumb person can do, in this situation? Would changing the air filter do anything...I think I can manage doing that. How hard is it to change a fuel filter?

    cprince, i don't know how to answer that because the only time it shakes is when I have the brake on, cause it only does it at stops. it doesn't shake when i am actually driving down the road, or at least not enough that i can notice it like i can while stopped. and i drove it a little tonight and it definitely shakes worse after the car has been running for awhile. it seems like the warmer out it is, the worse it shakes. car doesn't overheat or anything, antifreeze level is good.

    i dont know what other details you may want. spark plugs to my knowledge have not been changed at least since my wife bought the car(it was hers before we met), so for sure not in the last five years.

    can you point to a good how-to on changing plugs for a 00 neon?
     
  9. Kadarin

    Kadarin Lifer

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    Loose/broken engine or transmission mounts?
     
  10. brblx

    brblx Diamond Member

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    does the car have a tach? if the engine rpm is dropping considerably at a stop, it's probably related to the throttle (and IAC) or engine vacuum.

    fuel and spark issues would be more likely to manifest themselves under load. if the engine runs fine under load and at speed, it's probably a vacuum leak or throttle issue. clogged PCV system can also have a similar effect.
     
  11. boomerang

    boomerang Lifer

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    Take it somewhere. With no experience or tools, there is a real potential of costing yourself more than if you took it in. Your savings to install plugs or an air filter will be insignificant. I don't feel they're your problem anyway.

    See if friends, relatives or co-workers have a shop they'd recommend.
     
  12. exdeath

    exdeath Lifer

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    ^

    Easy to test. While cruising, hammer the gas and let off quickly before the engine has time to respond. Does the engine buck around?
     
  13. RGUN

    RGUN Golden Member

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    Look up a how to on cleaning the IACV. Did you look into it? I mentioned it in the first post. The problem is only at idle correct? So it makes the most sense.

     
  14. murphy55d

    murphy55d Lifer

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    i havent had time to do anything yet. i looked for a diagram or something for a 2000 neon but didnt come up with anything. i dont know what an IACV even looks like.

    i may get the plugs and possibly wires changed anyway, i am sure they are about due, vibration or not.
     
  15. alpineranger

    alpineranger Senior member

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    IACV is on the throttle body. Look for the electrical connectors, there should be two: the iacv and the throttle position sensor (should be directly opposite to the throttle spring)
     
  16. murphy55d

    murphy55d Lifer

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    OK I located the IACV. Either Friday after work or this weekend I will take it off and clean it. I have been reading a little and you are supposed to use brake cleaner, but careful as to not get any on the electrical parts. then let it dry before re-attaching. Correct?

    Also looks like there may be some plastic casing which may be in the way of the second screw, will have to examine further.
     
  17. fanario

    fanario Junior Member

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    murphy55d, did you solve this problem? I'm having exactly the same issue. The IACV sounds like an easy fix. Were you able to clean it or did you have to replace it?

    Thanks!
     
  18. fanario

    fanario Junior Member

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    Ah ha! I unplugged my IACV, let it sit for a minute and replugged it in. Idle problem solved. What happened with me was the problem started after I had a very clogged air filter replaced. I suspected that the IACV had adjusted to working with the clogged filter and didn't reset to handle the increased air flow of the clean filter. Didn't have to clean the IACV or replace it. Just an electrical reset was all it took. 3 mechanics couldn't figure it out, but with your help here and a little guess work the shaking is gone. Thank you!
     
  19. soccerballtux

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    well there's your problem right there
     
  20. theunloader87

    theunloader87 Junior Member

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    did this ever get solved im having this issue and the iac is not it
     
  21. ThachAuto

    ThachAuto Junior Member

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    I'm having the same exact issue. Can someone chime in if they have found a solution? Thanks.
     
  22. phucheneh

    phucheneh Diamond Member

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    Well that's a couple odd bumps.

    Post a video or something. It's hard to know if your 'shaking' is due to low idle RPM (in which case, the issue is not shaking...it's low idle RPM), bad mounts, or just terrible running condition (i.e. massive misfiring).

    If it's at idle in gear but goes away while driving (also hopefully no CEL), it's probably mounts.

    Also, if you car doesn't have a tach, get someone to check idle RPM with a scan tool. I'm going to guess it should be 700ish in drive. There should be a spec somewhere. Below 600-650 or so, you're probably pretty likely to get some extra vibration.
     
  23. CraigRT

    CraigRT Lifer

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    Thread is old as dirt... For any Neon owners though, Neons.org is the place to go. You can search their site without an account. Great forum for knowledge.
     
  24. ThachAuto

    ThachAuto Junior Member

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    Thanks phucheneh for you response. It's true, it is hard to properly diagnose a problem unless you know the circumstance in detail. So here it is:

    The car:
    2001 Dodge Neon SE with 105K.

    Symptoms:
    The shaking is most prevalent when the car is in gear (i.e. "D", "2", "1"). It is there when the car is parked and idling in neutral but very minor. However when it is in gear and when you come to a stop at a light or stop sign, the steering wheel and other parts on the dash or in the dash is rattling like it is a pile of loose material attached to a rocket about to launch. When you accelerate and while you are driving the car is smooth as butter, no matter what speed you are at as long as you are moving/accelerating. I've also checked to see if the wheel shakes while in motion by taking my hands off the wheel momentarily and there is no vibration other than the normal.

    What I've done to try to remedy this problem and other standard maintenance:
    1. Replaced upper and lower torque mounts (both were torn), middle engine mount (rubber parts appear aged but in ok shape) and transmission mount (rubber parts appear aged but in ok shape)

    2. Changed spark plugs, spark plug wires and central ignition coil

    3. Oil and filter change, air filter

    4. Transmission fuid and filter change

    5. Cleaned idle air control valve and throttle body

    None of these things have fixed the problem. These are part of the normal maintenance I was going to do anyway but I don't want to start throwing parts at it until I get some input and hopefully good leads on what to tackle next. One thing I have not done and will do next is a coolant flush and change the thermostat. I've never owned a Neon before and notice that the temperature gauge takes a very long time to move up (over 20 minutes of driving still does not bring it to the middle). I'm not quite sure if that is where it should be at normal operating temperatures, but I suspect that the thermostat is stuck open. I doubt that this would cause the shaking, but who knows. The coolant flush is just another standard maintenance item, but maybe it will help if the car can actually achieve normal operating temperatures with a functional thermostat.

    I know this is long and winded, but I hope more information will yield more feedback. Thanks in advance.
     
  25. ThachAuto

    ThachAuto Junior Member

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    I forgot to mention in my last post that, I do believe that there is a drop in RPM when the car is at rest but while in gear. There is no tach, but I'm confident that I have enough experience working on cars that I can tell there is a drop in RPM as if there is a bad spark or misfires, perhaps minor enough as to not trip the check engine light. The car has never thrown a check engine light by the way. The drop in RPM is noticeable enough to make me feel as though it may stall, but it has never stalled. I'll do what you suggest phucheneh and get a scan tool to check the RPM when I get a chance, but this will only confirm my suspicion and I'm still back at where I started. If it is a drop in RPM, the things I've done and repair/replaced should have fixed the problem (i.e. spark plug, wires, central ignition coil, idle control valve and throttle body cleaning). What am I missing?