ZC.. hunting Idle problem Fixed Browntop/Blacktop

**SINISTR** · 13-03-2006 11:42 AM

hey All,

Don't know how many ppl here have a browntop ZC in their car.. but It also applies to blacktop ZCs.

When I bought BANDIT, it was hunting at idle *revs up and down* when it got hot... I knew it was something with the Idle Air Control Valve (IACV) thats at the back of the throttle body *narrowed that problem down heaps of times*.

This time after replacing a USED and corroded IACV *water pipes litelarly broke off when I tried taking the clamps off the hoses* - the problem persisted - there was no hot water getting through to the IACV..

I tracked it back to a blocked pipe at the fuel rail side of the water cooling system - unblocked it and its idling sweet as now!

So just a bit of advice for the others

if youre car is idling like mine was - check that your IACV is getting hot water and is operating correctly.

Mike

(CICV is my term for Cold Idle Control Valve)

**Mr. Focus** · 13-03-2006 11:50 AM

hmmm....would this also apply to a d16a8?? mine idles very much like you've stated

**SINISTR** · 13-03-2006 12:03 PM

Its quiet possible Mick, the only thing is - on the D16A8s the CICV is built into the throttle body. But do check after you run the car - that the pipes at the back are hot - actually check ALL the water pipes - if they are cold you know there is a blockage somewhere near them.

Reason why car idles like it does - is because its being tricked its Hot and Cold as hot air goes around the system but not the water thats meant to turn off the Choke (CICV)

**EuroDude** · 13-03-2006 01:24 PM

CICV? I think Honda call it an IACV (Idle Air Control Valve).

Anyway yeah the ZC D16A8 is the faster backtop version of the older Brown top, basically the same engine.

ps. Two other things to fix idle problems: screw in the FITV knob and clean the throttle body. Actually cleaning the IACV didnt help my idle problems at all.

**SINISTR** · 13-03-2006 01:44 PM

hehe - I shorted it to CICV... as I know its called Cold Idle - because thats the only purpose it serves - same thing tho :P

the IACV (CICV) valve does occasionally get stuck inside - the spring goes a bit funny and doesn't lift the valve. I just found that water not getting to it seems to be a common problem... ive had it happen on this D16A3 and also on GENONEs EW5 motor.

**Weq** · 13-03-2006 04:32 PM

its not called a CICV
its called a
FITV - Fast Idle Thermo Valve - under the TB and controls cold idle
IACV - Idle Air Control Valve - on the rear of the intake manifold. this controls hot idle and rev dipping from load.

**SINISTR** · 13-03-2006 05:07 PM

Cheers for clearing that up :P

**Weq** · 13-03-2006 05:53 PM

sorry for being pendictive but in the very unlikly a noob searches ur thread before posting his problems, he will find ur aronymn and be like wtf nothing in the service manual about it and google doesnt even know what this is.

**SINISTR** · 13-03-2006 05:56 PM

Originally Posted by Weq

sorry for being pendictive but in the very unlikly a noob searches ur thread before posting his problems, he will find ur aronymn and be like wtf nothing in the service manual about it and google doesnt even know what this is.

hehe - I understand ... :P i guess I made up my own term... still makes sense tho haha... I'll change my posts

**hotboxcivic** · 14-03-2006 01:21 AM

how much is the idle hunting?

**SINISTR** · 15-03-2006 02:58 PM

oh yeah - and another thing... very important

if you're working with water hoses and clamps... do check them for corrosion, hardened hoses, corroded clamps... replacement ahead of time if you notice something happening with them will save you heaps of headaches later on down the track for example being stuck on the side of the road when you're meant to be at dinner with your GF or on the way to an important work interview.

and always use good engine coolant in your cooling system - not tap water...