Ok my car has been having a idling problem for a while now. At first it was idling up and down real hard between 3000rpms and 5000rpms. And was throwing code 41 o2 (sensor heater circuit fault) and code 7 (throttle position sensor circuit low input). Well i replaced the tps and re-calibrated. I had it set with the throttle closed it read on a ohms, 5.0v and with throttle open 4.7v. I reset the ecu and the problem remained. Then a guy i know noticed the wrong plug was plugged in the idle air control valve. After changing that it changed the way it idled. It now idles really jumpy at 1500 rpms. Also read the codes again after that and it then read, code 14 idle air control system fault and still the o2 sensor code. So tonight i removed the iacv and cleaned it with carburetor cleaner for about 2 hours. I also cleaned it out with a air compressor and let it dry for a while. I then reinstalled it, reset the ecu, turned the car on and the problem remained. But when reading the codes again the idle air control sytem fault code went away. The o2 sensor code remained however. So now i'm lost, I really don't think that o2 sensor code would trigger that but i'm not sure. Can anyone give me any advice on what i should try next? Oh yeah this is a 97 civic dx with a 94 jdm b18c swap, motor is converted to obd2. And is ran by a obd2 p72 ecu.

 

anyone?

 

you need iacv fix. your 97 dx has a three wire iacv plug in the stock dx harness.the p72 ecu needs to read a 2 wire plug to function properly. i have the same problem in my 96 dx coupe. our problem can be soulved b using a ex vtec harness. there is a post in the hybrid section for this and its step by step how to wire it up.

 

Thanks man. I'm looking into that now actually. I had already checked that before i posted this. And by looking at the ecu it appears the pinout has been done? I made a big mistake in paying to get this done. I saw the one write up on technet.ff-squad.com. If that is what you are talking about.

 

tha_badguy has the answer. thats his screen name find him somewhere in this forum