Hello,

I have a 2000 Civic with a B18C swap, I had purchased the car with it done, it used to be OBD2 and i have recently changed to OBD1 using a Rywire harness and chipped ECU from them. it has a Idle issue it jumps between 1100-1800, it did it both OBD2 and now with OBD1.

I have tried

cleaning IACV
new IACV
TPS tested, .49v-5.0v
vacuum leaks smoke tested nothing to be seen
all grounds have been changed to 0g wire all sanded and cleaned
new O2 sensor
MAP sensor seems to be within spec
new timing belt
all new coolant, doesnt seem to be any air in it

the car has no Fast Idle Valve.


things I have noticed

-cold or hot it will do it (more when hot)
-if i load up the motor, foot on brake, slowly release clutch i can sometimes get it to stop doing it bouncing stops, it then idles around 1100.

i may have missed some stuff

any suggestions or help of what to try would be very apprciated at this point this thing is driving me crazy!


Derek

 

So, the old OBDII ECU also had the fluctuating idle? Would it fluctuate the exact same?
That's weird, I have a chipped Rywire ECU for my H22 and it fluctuates too, although not nearly that much. May just be my larger injectors needing a tune. Is the motor modded in any way?

 

I had problems with my b18c1 with a JDM obd2 ecu That would jump from 1500 to almost 4000. I couldn't get it to stop until I completely rebuilt the engine.
You might want to get an FITV though. That's one of the things I replaced in my rebuild.

 

yes both the OBDII and OBDI ecu are fluctuating, the OBDI is by far less.

I have since played with my idle screw, now i dont know much about these things and the effect it may or may not have, but i turned the screw to the point of being open roughly a quarter turn, it is now not jumping as often and when it does start to its between 1000-1250 roughly.

as far as the FITV valve goes, i dont even have a place to stick one, i believe the throttle body i have is factory, but never had the spot for it.

 

What injectors does it have? Like I said, I have larger injectors, and it idles similarly just because it needs a tune over the chipped basemap. If you have aftermarket injectors, that could be the problem. If not, I got nothin :/

 

I have been trying to figure out what injectors are in it, there are no identify numbers on them, so been trying to search pictures see if i can come up with anything

 

I would check the o-ring on the idle screw.

 

so an update to this.

i have since swapped throttle bodies, re set TPS (with a new one)
still have the idle issue, something i did notice, and its not every time it works but if i turn the heat off the idle will some times stop bouncing, when it is back on it starts again... also turning stereo up can at times trigger the fluctuation...

which doesn't make sense that an electrical load would trigger it?
all my grounds are good and have been sanded at contact points and upgraded to 0g wire.

i do have a new H/O alternator coming in today that ill be installing this weekend i hope, not to sure if this could even be a alt issue though

 

yet another update


i am throwing code 14, i have tried 2 IAC's at this point

is there a specific one for the B18? or should any work?