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Thread: Idle issues

  1. #11
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    Quote Originally Posted by Bitsyncmaster View Post
    Try backing off the curb idle screw (lower screw on throttle arm) which also may need the idle switch screw to be backed off if it bottoms out on the idle switch.

    If you find like I did that even with that curb idle screw backed all the way out the idle would still climb after the engine warmed up, you may have the bad deceleration springs like I had. Once I replaced the throttle assembly that fixed my high idle.
    Quote Originally Posted by Morpheus View Post
    I had the same issue. I changed out my throttle butterflies with soft decel springs with newer, stronger ones and my idle went back to normal.
    OK Guys, thanks for the input. After checking the curb idle again it does appear the problem may be the the decel springs. Everything else seems to check out when I look very closely. After further testing it appears that the O2 sensor is working, the Lambda system is working, the idle motor seems to be working, and when the car warms up, the idle still goes up to around 1500 rpm.
    Can I actually find new springs? Someone told me I have to replace the entire assembly. Morhpeus mentioned soft springs. Where do I get those? I kind of want to be ready when I pull the little W pipe off. I'm open to hear some ideas. Thanks again.

  2. #12
    Senior Member Bitsyncmaster's Avatar
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    Here is what the bad springs look like. Good springs have evenly spaced coils.
    Attached Images
    Dave M vin 03572
    http://dm-eng.weebly.com/

  3. #13
    Senior Member Morpheus's Avatar
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    Josh at DPI was able to sell me a set of butterflies with good springs. I'm not sure if they were reconditioned or just good used parts, but they worked. Give him a call.
    Brandon S.

    2014 Honda Civic EX
    2007 Volvo S60R


  4. #14
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    Quote Originally Posted by Bitsyncmaster View Post
    Here is what the bad springs look like. Good springs have evenly spaced coils.
    Here are my springs. One looks worse than the other, but I also noticed that if I depress the one that looks the best it seems to have a lot of play in the hole and doesn't return with the copper end in a centered position.decel_spring_1.jpgdecel_spring_2.jpg

  5. #15
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    Quote Originally Posted by Morpheus View Post
    Josh at DPI was able to sell me a set of butterflies with good springs. I'm not sure if they were reconditioned or just good used parts, but they worked. Give him a call.
    Thanks, My springs don't look good so I'll talk to Josh at DPI.

  6. #16
    Senior Member Bitsyncmaster's Avatar
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    Quote Originally Posted by funkstuf View Post
    Here are my springs. One looks worse than the other, but I also noticed that if I depress the one that looks the best it seems to have a lot of play in the hole and doesn't return with the copper end in a centered position.decel_spring_1.jpgdecel_spring_2.jpg
    Yes those springs are most likely the cause of your problem. You can just seal up the holes in the plates but then you get pretty bad under shoot of the idle RPM.
    Dave M vin 03572
    http://dm-eng.weebly.com/

  7. #17
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    Quote Originally Posted by Bitsyncmaster View Post
    Yes those springs are most likely the cause of your problem. You can just seal up the holes in the plates but then you get pretty bad under shoot of the idle RPM.
    Yes, and I think I read that you had worked on that on your programmable ECU. Did you get that perfected? I read another post where a guy took the springs out and plugged the hole, then bent the micro-switch so it would activate on before complete De-throttled and he said this seemed to take care of the undershoot by allowing the idle motor to turn on at the end of the deceleration.

  8. #18
    Senior Member Bitsyncmaster's Avatar
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    Quote Originally Posted by funkstuf View Post
    Yes, and I think I read that you had worked on that on your programmable ECU. Did you get that perfected? I read another post where a guy took the springs out and plugged the hole, then bent the micro-switch so it would activate on before complete De-throttled and he said this seemed to take care of the undershoot by allowing the idle motor to turn on at the end of the deceleration.
    Good memory

    I have been running the blocked holes in the throttle plates for two years but I still occasionally get an under shoot more than I like. I decided I would go back to the OEM setup with the springs rather than put more effort into the software. Now if there was no source for good throttle assemblies, I would put more effort into the software changes.
    Dave M vin 03572
    http://dm-eng.weebly.com/

  9. #19
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    Quote Originally Posted by Bitsyncmaster View Post
    Good memory

    I have been running the blocked holes in the throttle plates for two years but I still occasionally get an under shoot more than I like. I decided I would go back to the OEM setup with the springs rather than put more effort into the software. Now if there was no source for good throttle assemblies, I would put more effort into the software changes.
    Thanks, rather than plug the holes I think I'll just order the refurbished throttle body from DPI and send the core to them.
    I think this will solve it and appreciate your help. I'll post the results once I get it in.

  10. #20
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    Did you ever get the rebuilt throttle bodies in?

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