Hondata

Hi,
I have a B18C engine transplanted to my EG6 (2-door Civic).

The warmed-up idling rpm with aircon off is high at 1,400-1,500. Even if I move the IAC slider to the extreme left, the rpm is still high at that range.

When air con is off, rpm drops to ~900.

I tried playing with the cells in the map too but to no effect.

AFR at that high-rpm idle is 15.5.

Questions
1. Can someone teach me how to get the idle rpm down to say 1,000 with aircon off?

2. If I managed to get it down to 1,000rpm, will idling rpm be affected once I on the aircon?

3. Should I be playing with the idle nut at the throttle body?

Setting the Idle Speed
To adjust the idle speed:
may need to adjust fuel table


1. Warm up the engine.

2. Set the idle speed to 850 rpm and move the duty cycle adjustment to the middle.

3. Unplug the idle valve.

4. Adjust the bypass screw until the engine runs at 450 rpm. If you can not reduce the idle to 450 rpm, then you have an air leak. Fix this before proceeding. If the engine will not run with the idle valve disconnected then your bypass port is clogged. Fix this before proceeding.

5. Plug the idle valve back in.

6. Clear the idle valve error. You should now get a smooth idle at 850 rpm.

7. Increase the engine speed to 2500 - 3000 rpm and abruptly let off the throttle. If the engine speed dips below 850 rpm, move the duty cycle slider to the right. If the engine speed hangs above 850rpm for some time, move the duty cycle slider to left.



Some engines prefer 900 or 950 rpm idle speed.

OSracer,
I read that instruction too.

The problem I have is that I cannot adjust the idling too low. The idling AFR at the current high rpm is quite lean at 15-15.5.

To adjust it lower means I have to lean the cells further so rpm will drop.

Is there another way to lower the rpm to 850 safely?

All,
This is the map.

15-15.5 is not "quite lean" at idle speeds.
That should be fine, actually, unless you're running some insane comp and timing that's making you knock when only that lean.

Every car runs a little higher idle when running AC.
If the 15 AFR is really bugging you, modify the cells at the RPM and load you're seeing it hit those values at (add fuel).

kinetics wrote:15-15.5 is not "quite lean" at idle speeds.
That should be fine, actually, unless you're running some insane comp and timing that's making you knock when only that lean.

Every car runs a little higher idle when running AC.
If the 15 AFR is really bugging you, modify the cells at the RPM and load you're seeing it hit those values at (add fuel).

kinetics,
I managed to lower the idling rpm to about 1,200 without aircon. AFR is about 15.5-16.

But, when air con is on, rpm drops to about 900 and car shakes probably becos rpm is too low or engine mounting is too hard and hence car shakes.

Anything I need to take note?

Any advice on the map?

u really should post datalog & list any mods to motor or is it stock?

post brand and size of injectors too..........

fly_n wrote:u really should post datalog & list any mods to motor or is it stock?

It is B18C with Crower Stage 2 cams and aftermarket valves/springs and CP pistons. The rest are stock.

I will post datalog later.

thething96 wrote:post brand and size of injectors too..........

Injectors are stock at 240cc.