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IAC Valve Cleaning

Discussion in 'Engine Tech / Drivetrain' started by drekoe, Mar 15, 2008.



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  1. drekoe

    drekoe New Member 5+ Year Member

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    hey guys. have a 97 ek d16y7 (119k miles.). 2 days ago i decided to clean my IAC Valve. also removed the TB to clean it. while i was at it, i decided to install a new pcv valve (easier acces to it). after installing the new pcv valve and cleaning the iac and tb, i installed everything back including a new tb gasket. didnt start the car up right away. today when i started it, it was idling high then came down a bit and now the idle is crazy. it drops and goes up again continuously. already reset the pcm. anybody with the same past experience? any ideas what the problem is? oh and its not throwing the CEL light.

    i dont get it. you clean one part and it turns out to be worst.:roll:
     
  2. fronomo

    fronomo New Member Registered VIP 5+ Year Member

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    did you use carb cleaner and like a tooth brush? also, if you did, did you let it dry out completely before mounting it back up? make sure have all vaccum hoses connected as well and listen for any leaks. i'd also check the coolant for air pockets
     
  3. hardcore97

    hardcore97 Hard Core Registered VIP 5+ Year Member

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    sounds like a vacuum hose is loose. thats what mine did when i accidentally left one off.
     
  4. drekoe

    drekoe New Member 5+ Year Member

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    yeah i used STP throttle body and intake manifold cleaner. i let it sit for a while to air dry. then i mounted the parts back on the car, didnt start the car right away. left it like that for 2 days yesterday morning was the first time i turned it on since the cleaning. dont know if this might have anything to do, but i dumped 1/3 of sea foam into the crankcase. about the coolant air pockets. i read a similar post. but with everything being fine, can that cause idle like that? it goes up, then down and just stays like that. when removing two coolant lines from the iac, a bit of coolant spilled. this must be where it got the air from but do i need to get some new coolant?

    also on the d16y7 iac, when cleaning. i removed the housing that has the connection. when removing it to clean it better, i saw like a magnet type of cylinder. should this piece never be loosened and taken off?
     
  5. drekoe

    drekoe New Member 5+ Year Member

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    which one exactly was the one you forgot to connect? did you also clean your iac?
     
  6. fronomo

    fronomo New Member Registered VIP 5+ Year Member

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    are you saying you actually took off the plate that is connected to the valve itself? i usually just spray it out and use an old toothbrush to get what i can. hasn't given me any issues. as far as coolant air pockets, you can get them when you unplug and re-install coolant hoses. you have to remove the radiator cap, add coolant until it is all the way full if needed, start the car, and then you should start getting air bubbles. each bubble will cause the level to go down a little, so just add it back until there are no more bubbles and the coolant starts to overflow the top.
     
  7. hardcore97

    hardcore97 Hard Core Registered VIP 5+ Year Member

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    it was one on the back of the engine that accidentally got knocked loose. not sure which one exactly i didnt find it someone else did and reconnected it so idk which one it was
     
  8. drekoe

    drekoe New Member 5+ Year Member

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    plate?? got some pics. today i decided to give it another shot. took the whole tb apart. i dont think its a vacuum leak because all hoses were connected. (brake booster, fuel pressure regulator, pcv hose, and the hose above the pcv)

    [​IMG]

    the tb taken apart.. when i cleaned it out, i removed the map sensor and the iac valve. couldnt remove the tps because theres no bolts on it.

    [​IMG]

    iac valve. the part i took off was the light green. inside it has a type of magnet. you can see its clean as well as the tb

    [​IMG]

    as for the radiator. i removed the cap and it threw out some coolant (before removing everything). the coolant level started to go down when i unbolted eveything. the cap was off. i guess it started filling in that empty air.
     
  9. fronomo

    fronomo New Member Registered VIP 5+ Year Member

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    so did you do the process i described when you put everything back together? filling and burping the radiator?
     
  10. drekoe

    drekoe New Member 5+ Year Member

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    not yet i just got back from bolting everything back on. 3 days ago when i first removed the coolant lines from the iac, it threw out a bit of coolant. today it threw out more because i took off the radiator cap. so the sea foam has nothing to do with this right? im a bit confused on what you said. ok right now the level of the coolant went down. so i should add more coolant till it tops off. radiator cap on or off? then start the car for how much time? then turn it off and check the coolant level? if needed add more? is this how to do it?
     
  11. slowcivic E G

    slowcivic E G bla bla bla Registered VIP 5+ Year Member

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    did you happen to replace the little rubber gasket?
     
  12. HiPWR Racing

    HiPWR Racing JDM Whore Registered VIP 5+ Year Member

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    u have to replace the iacv gasket?
     
  13. drekoe

    drekoe New Member 5+ Year Member

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    gasket was still in perfect condition. no cracks. just reused it again
     
  14. slowcivic E G

    slowcivic E G bla bla bla Registered VIP 5+ Year Member

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    people will tell you that everytime you remove the IACV to replace the gasket with a brand new one. alot of people have problems with surging idle.
    ok, just an option, i too have never had a problem reusing the original gasket but i know people who have.
     
  15. drekoe

    drekoe New Member 5+ Year Member

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    thanks for everyone's feedback. and im glad the car is working now. an oil change was planned for this past weekend. could't do it because of the idle problem. i dont really know where the problem came from. i did many things today. oil change, new oil filter, checked spark plugs, re installed them (they were still good). i installed the old tb gasket. it was in good conditions. the new gasket which i installed when the problem came up, is a bit different than the original (dont know if this has anything to do with the high idle). oh yeah and i also had to adjust the idle screw. idle was a bit high with the clean tb, but nothing compared to the other crazy idle. and yes i did that coolant procedure you described. topped off coolant, started the car. then got out all the air bubbles. did that about 3 times. car was running smooth. :D

    if anybody goes through the same problem while cleaning their iac valve let me know ill be glad to help out.
     
  16. fronomo

    fronomo New Member Registered VIP 5+ Year Member

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    ^sweet
     
  17. riceboy89

    riceboy89 New Member 5+ Year Member

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    hey i just had a quick question about the process of removing the iacv.

    do you have to drain all the coolant out of the car before cleaning it out?
     
  18. drekoe

    drekoe New Member 5+ Year Member

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    you dont have to. just disconnect the lines. have a can to catch what will spill out. oh and make sure the radiator cap is off when you do this.
     
  19. PLATUDO

    PLATUDO New Member 5+ Year Member

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    men i have a problem with my tps i think,beacuse if u leave the car in 1200 rpm, it starts to accelerate up and down like if it has some problem.....im not exactly sure that is the tps so my question, what could it be??? .... it sounds like ba ba ba ba
     
  20. turboyourcar

    turboyourcar New Member 5+ Year Member

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    yea i have the same problem but with an addition of the ecu is clicking...one way that the service manual says to check to see if u have a vacuum leek is when u start ur car it its reving up and down (ba ba ba ba) and u take either ur thumb or two fingers and u plug up the holw right above ur butterfly and ur engine continues to idle wierd u have to then check for vacuum leaks at the pcm valve, pcv hose, evap canister purge valve, intake manifold, throttle body, and lastly the brake booster hose. ( i have a 2004 civic d17a1) ut thats what the sevice manual says,

    i did this and the idle proble was fixed as long as my finger pluged 100% of that whole not allowing any air to go threw, may try it a couple of times too make sure there is consistance
     


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