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idle control valve

Discussion in 'Civic and CRX - EF' started by vg_Ace, Jan 26, 2008.

  1. vg_Ace

    vg_Ace New Member

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    Hopefully someone will be able to help me with this and I will be able to avoid taking it into the honda dealership. Everytime I drive my car and it gets warmed up and i pop it into neutral it idles weird. It kinda jumps from 1500 to 1000 and then back to 1500 and then drops to 1000. It just keeps jumping up and like the engine is trying to hold it but then it drops and raises again. Has anyone had this problem before? I heard something about a idle control valve. Could this be the problem?
     
  2. YBLEGAL

    YBLEGAL Regular Member w/ Cheese

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    First it sounds like the old bubbles in the cooling system thing.

    There is a valve called the Fast Idle Thermo Valve. it's for raising your idle when your car's cold. when the coolant in your engine reaches a certian temperature, it causes a diaphram to close the FITV. which lets your motor idle at normal ~800rpm. the bubbles slosh around and make the FITV open and close because the bubbles are a colder temperature than the coolant. So try bleeding your coolant. The bleeder screw for the coolant is behind and under the distributor.

    Or, try cleaning your IACV.
    How To: Clean Your IACV - Team Integra

    There's one more thing relating to the FITV you can try, but i'd say these are your 2 most probable causes. if they dont work i'll tell you the other
     
  3. tunercrazed

    tunercrazed HS Official Hippie

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    I doubt its your valve, my crx needs one and the rpm's don't really jump around that much and it does in drive and park as well as neutral. I'd listen to YBlegal, what he said sounds plausible.
     
  4. vg_Ace

    vg_Ace New Member

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    ok so I was able to take off the IACV and clean it but I can't locate the bleeder valve. Can you give more detail or a picture?
     
  5. Aleaf.CRX

    Aleaf.CRX Hates Cunts!

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    Actually, I just had the same EXACT problem fixed today. My RPMs would go up to 2000 sometimes, then drop all the way down to 1000 and go every number in between. I know what I did, but I don't remember the names of everything, cuz I'm new to car stuff, so bear with me, k?
    Depending on what Honda you have, I don't what you drive... well, I'll just go with how my car is and you can adjust to that.
    I have an 89 Honda CRX, and the throttle body (?) is located to the left and under the fuel injector. There's a cable connected to that. If you pull on the cable (the throttle I think) your engine will rev. Just to the right of that is a screw-looking thing. Using a screwdriver, turn it either right or left to go higher or lower.
    I did that to mine today and the idle doesn't jump around and it stays around a steady 1000 RPMs.
    I'm sorry I didn't know the names to stuff, but I hope that helps your problem! If you want, I can explain it a little better and look up the names to things so you know where you're at, just let me know.
    Good luck.
     
  6. 93civicracer

    93civicracer Oh, I do a little here and there.

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    The bleed valve for the coolant (at least for my d15b vtec) is on the upper radiator hose outlet the one you can see right on the front of the head. It should look like a (12mm) nut, not real thick, and should have a hole on the top in the middle. When you loosen it, coolant flows out. Loosen it and it should come out all bubbly then after the bubbles are gone and it's just a stream of straight coolant, tighten it and refill if you have to.

    This is how it is in the factory service manual and I just refilled my coolant today after I drained it all while fixing a leak.

    And I don't know about yalls cars but the specs for my idle and most of all D-series motors' are supposed to idle at 650 rpm +/- 50. Mine is right around 650 after I bled the coolant :D.
     
    Last edited: Jan 26, 2008
  7. YBLEGAL

    YBLEGAL Regular Member w/ Cheese

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    [​IMG]

    I hear this question a lot... :)
     
  8. vg_Ace

    vg_Ace New Member

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    Ok so after i cleaned the IACV and drove it I immdiately noticed a difference. First of all it idles Really low now. Which makes me think I just need to adjust the idle. But as for the jumping it has completely gone away. Thanks for all the help. btw what is a good idle Rpm for a 91 crx HF? my chiltons says between 450 and 550 but that seems low.
     
  9. Aleaf.CRX

    Aleaf.CRX Hates Cunts!

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    Mine's at about 1000 RPM, that seemed about right to me. Any lower than that and my car shudders.
     
  10. 93civicracer

    93civicracer Oh, I do a little here and there.

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    Go by what the manuals say. My 93' civic idle'd at 800-1000 and I thought that was right, but then when I looked at the manual it said it's supposed to idle at 650 +/- 50 rpm. After I bled all the air from the coolant, the car started idling dead on. It's right at 650.

    But I'm still throwing a code 14, iacv, with a brand new iacv installed and I have no idea why.
     
  11. YBLEGAL

    YBLEGAL Regular Member w/ Cheese

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  12. Aleaf.CRX

    Aleaf.CRX Hates Cunts!

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    Yeah, actually mine is kinda crazy again. Anyone know what the exact problem is, or if it's the computer....??
     
  13. 8ballsin

    8ballsin New Member

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    i have the same problem on my 90 crx si D15B2 You bleed it while the engine is running correct?
     
  14. YBLEGAL

    YBLEGAL Regular Member w/ Cheese

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  15. 90_EF_Hatch

    90_EF_Hatch Señor Member

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    adding my car to the list of cars with this problem :)


    does it hurt your car??? just curious.
     
  16. YBLEGAL

    YBLEGAL Regular Member w/ Cheese

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    does a bad idle hurt your car? or does bleeding coolant hurt your car?
     
  17. 90_EF_Hatch

    90_EF_Hatch Señor Member

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    bad idle... hahha ...

    im sure bleeding the coolant isnt bad.

    but i have got a fucked up radiator to begin with so i dont think i could fix the problem without replacing my radiator first.
     
    Last edited: Feb 27, 2008
  18. YBLEGAL

    YBLEGAL Regular Member w/ Cheese

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    ah that sucks.

    idk if it hurts it or not. maybe depends on the type of bad idle. high idle may actually be better for motor longevity since it keeps oil pressure up, but of course bad for fuel economy in the city. low loping idle could be hard on it. idk.
     
  19. pappaj

    pappaj New Member

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    The idle that the chilton manual refers to I think is probably the base idle, which is adjusted a little different than your regular idle. For my motor it says 500 rpm for base idle and 800 +/- 50 rpm. Mine is a zc, I would just do a search for your motor everyone seems to have different opinions.
     
  20. LS_VTEC

    LS_VTEC you get the BRAKE

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    This is going to be really simple. Start the engine and let it idle until it reaches normal operating temperature. With the engine running, remove the intake and expose the throttle body. Look inside and you will see two holes on the throttle body inset toward the rear. The bottom hole is for the FITV and the top hole is for the IACV. Put your finger over the top hole with the engine running. You will feel suction. If the idle corrects itself with your finger over that top hole than your IACV is not functioning properly. Do the same for the bottom hole and see if the idle corrects itself there as well. If it does affect the idle (which I doubt), than the FITV is not closing. Usually, the plunger inside the valve comes loose. I did one on my first gen b16a a couple months ago. Idles fine now.
     
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