car idle drops very low as if its going to stall

[vtac_ej6]

hey guys i have a 98 lx civic sedan. 174k miles d16y7 with vtec y8 headswap. have manual y8 ecu, y8 injectors fuel rail, mani tb etc. headers back greddy exhaust and aem intake.

my issue is when i come to a stop my car will idle ok then every so often the rpms will drop down to the very bottom of my tach and then after a second it will surge back to about 1k rpms and idle normal till it drops again. there is no bouncing idle or any other issues i can think of. there arent any abnormal cels or anything. i have cleaned the iacv and tb and also found and fixed a vacuum line


any help would be appreciated

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[Failsafe88]

Hmmm i had that problem with mine like when i came to a stop. Of course i probably have different setup than you. However, i have hondata and ended up having to get into hondata a raise iac.

 

[gooddog]

Vaccum leak in your brake booster would explain the idle when you come to a stop.

 

[vtac_ej6]

well is that the case wheb the car is juat sittig therw idlig without the brakes emgaged?

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[vtac_ej6]

any other suggestions?

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[NLEFsedan]

Lamda prode might be giving some trouble to!

 

[vtac_ej6]

Lamda prode might be giving some trouble to!

whats?

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[Szady]

Check your cam timing. How does it run? Does it feel like it lacks power? Other than being a slow D16...lol. Also, check for vacuum leaks.

 

[vtac_ej6]

Check your cam timing. How does it run? Does it feel like it lacks power? Other than being a slow D16...lol. Also, check for vacuum leaks.

idk seems like 120hp to me lol. idk its my first sohc. but it seems like it pulls hard to me for what it is.
i already fixed 2 vaccum leaks. doesn't seem to be anymore

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[Szady]

Does it happen when your on the brake?

 

[vtac_ej6]

Does it happen when your on the brake?

umm i guess. i mean if the car is just sitting there with the ebrake on it does it. so shoild i start it and block it so it doesnt roll and see if it still does it with out any brakes applied

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[Szady]

Did you check your brake booster vacuum line? I know sometimes if removed enough they become lose and easy to take off. Could be causing a leak without you knowing it.

 

[vtac_ej6]

ill give that a check and report back this week

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[vtac_ej6]

well today i let it run without applying the brakes or ebrake engaged and it stil did it

here is a video i recored today
http://www.youtube.com/watch?v=vqne41eHz6Y&feature=youtube_gdata_player

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[vtac_ej6]

bump

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[vtac_ej6]

help still have this issue

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[Szady]

Have you found any vacuum leaks? Double check your cam timing, as well as your ignition timing.

 

[Failsafe88]

IAC as i stated before its the same problem i had.

 

[vtac_ej6]

Have you found any vacuum leaks? Double check your cam timing, as well as your ignition timing.

i have checked for vacuum leaks and found and fixed 2. i was not able to find any others

IAC as i stated before its the same problem i had.

i did clean it as well as tb still have the issue. i might just bite the bullet and buy the iacv and hope it fixes my issue. i just hate to spend 200 bucks and find i dont need it



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[Szady]

FInd a used IACV...