"Idle Re-Learn"... this is what i typed in the search, and only 2 threades came up that didn't help. Is this not that important? How do you do it?

 

In general, not just Nissans, the engine controller will relearn its idle and general optimum running conditions in anywhere from 20 minutes to 3 days. Depends on the car, weather, driving style, and if the engine is given time to...well...idle, or not.

Start up, drive away, it might take 2 days to get all parameters reset. Start up and idle for 5 minutes, and you might be done in short order.

I guess the question for you is: why are you concerned about the idle? did you remove the battery cables for longer than 20 minutes? or is there something else that is making you want this info?

 

I am getting the cxj spacers, and the instructions said re learn the idle, so i was curious... but now i got it, just sit tight and drive it and it'll do it on it own.. thanks for your help.

 

Oh no no no no noooo....

Idle relearn procedure to be performed ANYTIME anything about the intake is removed, changed, modified, etc...

Proper conditions have to be met:

Engine warmed up fully (take a 10 minute drive)
Steering wheel pointed straight ahead
Car sitting on level ground
Fuel level at least 1/2 tank full
ALL accessories OFF (A/C, fan, radio, headlights, interior lights, etc.)
If radiator fans kick on at any point, this process will not complete...so warm engine, but not too warm
No DTC stored in ECM
Must have a stopwatch to time this correctly

With engine and ignition OFF, turn ignition ON and wait 5 seconds (don't time this step, it's really not imperative that it's exactly 5 seconds...just round about)

Rapidly press the accelerator pedal completely to the floor and release it completely 5 times QUICK

Get a stopwatch - you'll need it now. Wait exactly 7 seconds.

Fully depress accelerator after the 7 seconds elapse and keep it held to the floor. I find that once timer reaches around 6.7 seconds or so is a good time to hit it to the floor. Even a fast foot takes .2 or so seconds to make it to the floor.

Within 10 seconds the SES light will start flashing (at this point, if you release the accelerator pedal, it is in diagnostic mode and it will flash out any error codes stored in the ECM...but don't release the accelerator pedal...just keep it held to the floor).

Keep the accelerator pedal held to the floor for a total of 20 seconds. At the 20 second mark, the SES light should stop flashing and remain lit solid.

Within 3 seconds of the SES light staying lit solid, release accelerator pedal and immediately press brake pedal and start engine. Basically as soon as you see it stop flashing and stay lit up solid, start the engine.

Now, it is in idle relearn mode. Let it idle for ~ 20 seconds. Rev engine several times and verify that it falls to a smooth idle.

Done.

So basically it goes like this:

ignition ON

accelerator pedal DOWN UP DOWN UP DOWN UP DOWN UP DOWN UP quick quick.

Wait 7 seconds

Pedal to floor

Wait 10 seconds and SES light starts flashing

Wait 10 more seconds and SES light stops flashing and lights up solid

Release accelerator pedal and start engine immediately

Prepare to get frustrated....it takes multiple times to get the timing exactly right because it has to be EXACTLY 7 seconds. Basically, if you keep the timer running and you don't see flashing of the SES light begin within 10 seconds (it just stays lit solid even after 11 or 12 seconds after you're holding the pedal to the floor) then you need to just turn ignition OFF for 10 seconds, then turn ignition back ON and restart the process. Even with practice, it takes me 5 or 6 times in a row to get her to cooperate.

Also of note....something that needs to be done prior to the idle relearn is the accelerator pedal released position relearn and the throttle valve closed position relearn. Super simple.

Turn ignition ON for at least 2 seconds

Turn ignition OFF for at least 10 seconds

REPEAT

REPEAT

Done....now do your idle air relearn.

Late,
Trav