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Discussion Starter #1
i've had a bouncing idle for awhile now, and i can't seem to find out whats wrong with it, i've replaced both the fast idle valve,IACV, i've sprayed every single vacume line i could see with WD-40, and still same thing, i sprayed both the top of the intake manifold gasket, and the throttle body gasket and still nothing? what could it be??? i'm ready to pay and arm and a leg and just let the honda dealership take care of it?

and i have no cel's, coolant is full and all the air is out, i sprayed every line i could see and still nothing, and both the IACV and fast idle valve both worked before i changed the motor
 

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Discussion Starter #4
when i changed the motor, and it all worked fine before the swap (well before the head gasket blew in the old motor)
 

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It may be your O2 sensor. O2 sensors can be bad, and yet not cause a CEL code. I am having the same problem as you...where my idle bounces up and down. I have replace everything else, except the O2 sensor. So I will be replacing that ASAP.

My idle only bounces while the engine is at normal operating temperature.

ECU's read the O2 sensor to determine air/fuel mix once the O2 sensor has heated up, thus creating a closed loop operation (prior to the O2 sensor heating up, the ECU uses all other sensors to determine fuel delivery, open loop operation). I think I read closed loop operation begins once the O2 sensor is at 600 degrees Fahrenheit.

If the O2 sensor is bad, the ECU doesn't know if the car is running too rich or too lean. The bouncing idle is the end result.
 

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nonvtak ftw
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It may be your O2 sensor. O2 sensors can be bad, and yet not cause a CEL code. I am having the same problem as you...where my idle bounces up and down. I have replace everything else, except the O2 sensor. So I will be replacing that ASAP.

My idle only bounces while the engine is at normal operating temperature.

ECU's read the O2 sensor to determine air/fuel mix once the O2 sensor has heated up, thus creating a closed loop operation (prior to the O2 sensor heating up, the ECU uses all other sensors to determine fuel delivery, open loop operation). I think I read closed loop operation begins once the O2 sensor is at 600 degrees Fahrenheit.

If the O2 sensor is bad, the ECU doesn't know if the car is running too rich or too lean. The bouncing idle is the end result.
Indeed this is true. A good fact i forgot about.
 

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Discussion Starter #8
umm, i have already changed the O2 sensor, cleaned the IAT becuase the one on the Z6 manifold was bad, i put basilcy everything from my b7 manfiold (which it ran fine before swap) and yea i fixed all my CEL's and still nothing but tommrow i'm going to honda, hopefully they can find it quickly
 

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STTJ- But mine idles high then CEL comes on about 10secs after I turn the car on, and then starts to bounce, I know the 02s are bad thats the CEL code but you think just having bad 02s is going to make it do that?

What would you use to clean the IAT sensors? Carb cleaner?
 

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Discussion Starter #12
ok so i took apart my old fast idle valve, and where is the screw that everyone is always talking about i can't find it?
 

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Discussion Starter #15
nvm, i played around somemore is that big round white thingy, i was thinking it was like a real screw, now how should i go about adjusting this? all the way in, then back out like quarter turn?
 

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Brokedick Millionaire
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you've failed.......just like I have because I can't find my pics!

AS mounted on the car, the FITV hanging under the TB, the access cover faces the firewall. IT is possible to do the FITV tightening ON car, BLINDLY, if your dyslexic, half drunk, kidnapped, and have a clue WTF your are doing :)

If I had a FITV/TB in the garage I'd go take pics.........but I've failed there too as well.
 

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Discussion Starter #19
you know what sucks?

when the little screws on the plate BREAKS inside the hole, its awesome i have to say
 
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