How to Tune Idle in aem series 2

Now, we can finally start tuning your idle. The first thing you will need to do is set your “Idle FB Dead Bands +/-“ to -3000 and 3000. What this does is tell your ECU to make corrections to your idle when the RPM is off by 3000. In other words you are just telling your ECU to not make any corrections. This will allow you to calibrate your tune as precise as possible so the ECU does not have to work hard to correct the idle RPM.

After that step is completed, we will give some attention to your “ignition map”. The table/map represents your ignition timing throughout your entire engine operation. We will focus on idle. Most engines will idle between 500-1600 RPM and between -5 and -15 psi. I have circled the region you should pay attention to. You will want to leave your idle ignition timing at whatever your base map is set to which should be between 10-18 degrees. The idle region should be the RPM at which your car idles when it is fully warmed up. Ideally, between 800-1100 depending on how rough your engine runs. From 1100 and up you want your ignition timing to gradually go up to your “cruising ignition timing”. This can be different for each engine but it’s always a value much higher than idle. Refer to the pictures below to understand what I mean by the smooth transition.

Basically, just make sure that your ignition timing does not have any large or abrupt changes in it. Remember more ignition advance will raise the idle and if there are drastic changes your idle will oscillate and tend to shoot up when it reaches those large numbers.