So my honda is having an idle problem only at cold start and it idle surges from 1500-2000rpms for about a minute and then sits at like 1800rpms until it gets alittle warm then it idles at normal 450rpms. So ive been hearing that the Fast Idle Thermo-Valve could be the problem, and i have also heard that you can block it off.

Any info on this would be great. Thanks

 

That acctually sound pretty normal. All of my Hondas idle at about +/- 1800 rpms when it's cold.

FITV is supposed to raise the idle until the coolant warms up, then it closes and the IACV takes full control of idle air flow.

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Yup, it seems like normal operation for any vehicle actually

 

idle when warm should be about 800 +/- 50

 

I meant to say it surges from 1500-2000rpms when its cold and only lasts like a 1minute and then its fine, just idles at steady at 1800ish rpms until the car gets warm

 

My OBD1 B16A did that for years, never bothered me, but if it drives you nuts try cleaning the FITV. There are a couple of good DIY threads kicking around here that still have working pictures.

Normal. It's trying to get warmed up.


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'92-'95 Civic (with IACV connected)

D15Z1
Manual....600 +/- 50 rpm
Auto.......700 +/- 50 rpm

All others
Manual....670 +/- 50 rpm
Auto.......700 +/- 50 rpm

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Anybody ever bypassed the fitv tho?