Hondata

using s300 on jdm b16 in 94 hatch. in the morning when first starting the car it idles at about 1200 for about 15-20 sec then it surges, not a quick surge but a rhythmic between 400-1000, if i dont give it gas the car will die. i have replaced iac, coolant temp sensor, coolant is bled of all air in system, tps is correct. this motor has no fitv. does this have something to do with the basemap values for water temp? im stuck. dont know what else to try.


HELP!!

I'm not exacly sure from your description of your problem, but that same symptom or having a cycling idle where it bogs and and then IACV compensates, can also occur if you have a valve seat leak. (it's a form of air leak, much like losing air from the manifold/vacuum sources.)

Try completely blocking off the 2 ports under the throttle body.

arent these coolant passages? where would i reroute these to?

Just loop the hose so that it bypasses it.

The suggestion to block off the 2 ports under the throttle body are diagnostics.

ok. what should i be looking for to happen?

I have this ALMOST same problem, except that my car doesn't die if I don't give it gas. You need to adjust your Idle via a Helms manual first. Follow those directions and try to get your A/F to be 14.7 while you are setting your idle. Then you can troubleshoot your other problem of surging idle... which is the same thing that's happening to me (read - only when the car is cold)

ive tuned the idle to 14.7 already once the car is warm. ill try resetting base idle again.

I fixed my problem by tightening my FITV. Maybe you can look into this for yourself?

It might be about time you cleaned the iacv and the fitv. My Integra would always idle at about 2k when cold and I thought it was normal operation until I looked at the coolant temp idle settings in smanager. Cleaning the iacv and fitv fixed all my ilding issues.

motor does not have a fitv. and iac is brand new honda piece.