Fast idle

[fred92htch]

I posted this in the EG forum but have not gotten much help. Maybe some of you tech guru's can help. I put on a Skunk2 intake a while back on my GSR swap. When I first crank up the motor, my idle is at 2500 RPM's. It will stay high except for dropping to about 1200 then back up to 2500 till the motor warms up. After that it is normal. Is there an adjustment for this? Could it be a sensor going out? A month ago it would only fast idle around 1200- 1500 RPM's and has slowly gone higher. _______

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[BLK JDM]

Have you checked your sparkplugs lately. Worn out plugs may cause a high idle when the car is cold. Could be your Sensor or you may just need to adjust the idle on the intake manifold.

[fred92htch]

The thing idles at 3000 RPM's now. it will drop to 1500 every one and a half seconds and jump right back up.
I checked ALL vacuum lines and that's not it. I then thought it could be the IAC valve so I special ordered one and when it came in I put it on. DID NOT fix it.
So now I pulled off the intake tube and saw two openings inside the throttle body, before the butterfly. I covered one with my finger and nothing. I covered the other one and the idle fell right down to about 700 (normal). Now I am thinking maybe the Fast Idle Thermo valve.
Anyone have to replace this? Is there a solenoid or switch that controls this or is it strictly mechanical? Any help is appreciated.

[Aceman64]

What TB pulley are you using?


-Ace

[fred92htch]

DX. The butterfly plate does not move while this is all going on. A few weeks ago it was running fine and idle was around 700. I really feel it is air / vacuum related, not mechanical in reference to the idle screw for the pully.

[preluder]

im not sure i may be wrong but for my h22 I think that it may be the fast idle thermo valve. but soon i will change it. Right now i gotta drop my tank to change the fuel pump too much bogging for my h22 it loves gas and my accord pump isnt doing it.

[fred92htch]

Well, as of today I have talked to a shop and they told me the symptoms are either the IAC or the FIT valves. Either way it's gonna cost. I'll post if the FIT fixes it or not.

[Aceman64]

Try this. Look for the screw on the TB that limits the amount the butterfly is open at idle. Adjust the screw some. I believe you close it just a little. My friend had the same problem, thought it was the IACV and thats what it ended up being was the butterfly set screw.


-Ace

[fred92htch]

I FIXED IT! I went to a mechanic in town after work. Told him the problem. He said ANY time a cars idle starts going higher, it is always vacuum related (on Honda's at least). I was in my other car so he showed me one in the shop and what to do.
On the Fast Idle Thermo valve, there is a plate with two screws holding it on. Take the screws out, remove the plate and there is a spring loaded plunger inside with a ring around it holding it in place. There are two slots, one on each side of the ring. Use a small slot screwdriver to turn the ring and screw it back down into the valve cylinder.
On my Skunk2 intake, it is on the rear side of the valve, under the throttle body. Kinda hard to get to.
What happens is the ring starts backing out and opens up the valve more and more causing the idle to slowly increase over time. This is what controls your idle before the motor warms up. After the motor reaches operating temps the IAC then controls your idle.
I did this today and the thing idles like a dream. Took about 15 minutes. What makes me sick is buying a new IAC valve that I did not need. The mechanic said "You should have talked to me first". Cool guy.

Thanks for the input guys. I checked what you said but that wasn't it. I do appreciate you trying to help.

[jeremyEG]

i have the exact same problem!! im using the skunk intake and gsr t-body. is the adjustment thing on the intake itself or on the throttle body?? i turned the adjustment screw all the way down on the t-body and it did'nt help.

it jumps from about 1200 to 3000 till it warms up then idles at 2000 when warm. i thought maybee it was just my chipped ecu or my 8.8lbs flywheel, but i guess not.

[fred92htch]

The FIT valve body is directly under the throttle body, attached to it. There is a small hose for coolant (antifreeze) connected to it. The plate you have to remove is facing the firewall, it's about as big as a .50 cent piece with two small bolt / screws holding it on. The plunger is inside the body of the valve under the the plate.
I used a mirror to find it then almost laid on the motor to see what I was doing.
I had to turn the ring on the plunger about 3-4 turns before it snugged up.

[jeremyEG]

ok, i have it off right now and it wont tighten up. it just spins freely. its doing the idle even worse now with the plate off. but if i put my finger over the plunger it will vaccum and idle normally. so i guess i need to tighten it up.

any ideas on how to tighten it if it spins freely???? i can push it inwars a good bit. should i push it in an dthen try to tighten it????

please resopnd asap, im at work and would like to try to fix it before i drive home,

thanks in advance

[jeremyEG]

ok, i got it fixed

the spring was off its perch and i couldnt get the plastic piece to thread in. i pulled it apart and put it all back together and screwed it in firmly.

the car started and idled at 1000 no surging or high idle anymore!!!!!

and i thought i was stuck with it that way. ive been driving like that for almost 2 months now.

thanks again

[jeremyEG]

just curious, how do you like the ctr cams with the skunk intake? i think the gsr cams are not large enough for the mani. i was looking into getting some ctr's.

[fred92htch]

I really like them. BIG difference on the top end, above 5k. I think a little more low end too, like daily driving. I have not had it tuned yet but you can definately feel the difference. I'm very pleased.

[jeremyEG]

im going to get them as soon as i can afford to. ill most likely get the springs and retainers also so i can rev to my 8500 rev limmit. hoping to maybee break into the thirteens with them.

[Paradigm1381]

I have been dealing with the exact same problem (the surging at traffic lights and stuff) for 2 months now! You said that you were finally able to fix the problem by adjusting that FTR valve. I am going to try to fix my 95 civic Si (no mods) and I was just wondering if yours surged at all times or only when the car was cold, because mine does it randomly even after the car is warmed up. By the way, like Fred97GLE I also replaced my IAC valve to no avail. Any feedback you can give would be greatly appreciated.

[Cody]

I think you guys just gave me the information needed to fix the car of a good friend of mine - thanks for the info!

Just off hand - what is the going rate of a FIT valve?


Modified by Cody at 10:57 PM 8/12/2004

[SjCiViCHB]

Would that problem cause your car to idle crappy? sometimes when i start my car the Idle would jump up to 1500 then drop down under 1000 dramatically and it would sound like my car would die, but then the rpms jump up and it stays on then it comes back down and it sounds like it would die. Do you think i could fix that with what you did?

[SickAssLy]

my car does that too.ive tried everything you did except the FIT methode ill give it a shot thanks for the info guyz (HT rocks)

[kihun_cha]

shit mine was doing this about 2 montha nd im gettin pissed off.. imma have to try this tomorrow.. wish me luck fellas

[SjCiViCHB]

Does anyone have pics of this procedure? I can't find the FIT valve under my gsr throttle body... I also have a Skunk2 manifold.

[Sack Master]

I don't have any pictures of it but there is a water hose going in and out of it. It's right under the throttle body screwed into it. It's very easy to fix. I think 3 screws/bolts and its off. From there you can take it apart and clearly see the valve and how it needs to be screwed back in. I've done it plenty of times.

Had I gotten to this thread earlier thats what I would have told you to look at first.

[kihun_cha]

im running skunk2 manifold and i need picture to find da damn FIT valve.. pleaes pictures

[kihun_cha]

it's right next to iacv... and it's black..

but after u take it out what do you do? i need it asap


Modified by kihun_cha at 2:33 PM 9/16/2004