Fast Idle Valve

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Ok,

I have a b18c1 in a 94 civic dx. I'm having trouble getting it to start when the engine is cold and even when it is warm (takes 4-6 tries to get it to go when cold and ~2 when warm)

symptoms when started:

1. idles high by ~200 rpms irregularly
2. when i try to hold it at a certain rpm while in nuetral the idle sporadically drops ~100 or so rpms.


I've checked my Fast Idle Valve by checking the flow at the port in the throttle body opening, I've got strong suction when the engine is cold and weak suction when the engine has warmed up. Is it supposed to have any suction at all when warm? I've read that it should have "no flow when warm" and I'm getting a little suction when its warm...

I'm also going to take the IACV off and try and clean it but I've never done this before either and would appreciate any help or a link to another thread where this process is explained...

thanks
 
Does the idle surge even when the engine is warmed up? I just replaced my PCV valve and that solved my idle surge problem... and it was a cheap fix.
 
m also going to take the IACV off and try and clean it but I've never done this before either and would appreciate any help or a link to another thread where this process is explained...

Its located on the backside of your intake manifold, There will be two 1/4 inch coolant hoses running to it and 1 wiring plug.
Disconnect hoses,
Disconnect plug,
Then remove the two 12 mm bolts, Im not sure about clearance on a civic but in my GSR its kind of a tight fit, a ratcheting wrench may be your best route.
Clean the screen of any debris and slap it back on
 
well i took off and cleaned the IAC and the fast idle thermo valve seems to be working because it's letting air flow when the engine is cold and not flowing when warm but the car still is having trouble starting up...

Should I go and get a new fast idle valve and IAC even though both seem to be working?
 
No, thats the mistake I made, I have a super erratic high\low idle and I thought it was the IACV to, bought one new for $160 replaced it and that was not my problem.
 
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