Hi guys,

I know this topic has been discussed countless times, but I'm just after some clarity.
It seems I must have been doing more night driving since I last reset my ECU as my idle seems to be perfect with my headlights on, and when they turn off, within 10 seconds, the idle will have crept down to 500-600rpm.

What I have read is: Turn all electricals off and turn the car on and hold the RPM at 3000 until the radiator fan turns on, then off the gas for 5 minutes not counting fan time.

So I have a question -
Is the "hold the engine speed at 3,000rpm" only to speed up the process? Would it be just as effective for me to reset the ECU and then just let the car idle for 10-15 minutes, as long as the fan turns on a couple of times during the process?

 

I just let it idle, I don't hold it at 3000 rpms, but that's just me and I never had any issues.

 

 

I do what you do which is what Honda says to do in the shop manual.

I don't know the reason for it but Honda engineers are a pretty sharp bunch of folks (after all, they designed our S2000s) so there must be a reason for doing it the way they spec.

 

I dont recommend the holding at 3k rpm, i did it once and i got a code for something along the lines of a faulty sensor, so i got cel and and an eps light i think it was, basically the car thought the gas stuck on

 

The EPS CEL may come on if you are accelerating and not moving, but it usually goes away as soon as you start driving again.

If anyone really wants to do it by the book then disconnect the battery after a typical drive when the car is fully warm and you don't need to worry about holding the throttle at 3,000 rpm as the car will be fully warm.

 

The EPS does come on when you do the idle reset according to the factory manual but it's supposed to. It goes off immediately when you drive the car 20 ft or so.


Curious why folks don't take the 7-8 minutes it takes to do it like Honda specifies? If there were an easier, shorter way, I'm confident Honda would have sped'd that instead.

 

Well, wish i knew that when i was in my garage trying to search s2ki with my greasy fingers on my phone. Good to know . Rev away.

 

So I did the idle relearn. My car was idling perfect as it should (with the headlights off (where it used to be crappy idle without them on)). for about 4-5 days after doing the relearn.

BUT... It is now doing what it used to do, where my idle (once the car warms up) is rubbish, and nearly stalls (but doesn't).

I've checked the IACV and made sure it spins freely, i've swapped the MAP sensor, i've cleaned the throttle body (even though it's irrelevant) and i've had different intakes with the same results.
I've checked all the vacuum lines.
I'm puzzled as to what else it could be??

It just doesn't make sense that when I turn my headlights on, it idles like it should be with them off.
Usually people have issues with headlights lowering their idle, so that makes it near impossible for me to find someone else with the same issue online anywhere T_T

Another thing to add, which may help solve it?
Since the idle lowered down again, it now does a small 'struggle'? and the car shakes/quicky pulses as if i've turned the A/C on or something, as if it's struggling to idle on it's own.
Hard to explain, but it's happened twice now, and it doesn't bring the idle any higher afterwards...

And as explained above, the headlights being turned on will make this not occur...