Originally Posted by wroark
I'm no expert but I have gotten my idle to be pretty solid.
Some things I would try:
Idle --> Options Idle: Set your A/C on Delay to 1 or 2 seconds.
Increase your timing values in the 17.97 load row up to 30kpa , from 750 pm to 1500, to be around 12.5/13. Your timing map looks odd, like it was rescaled or something.
If you have a wideband, my AFR for a good stable idle is 12.5 or so. Really rich but it's rock solid.
There are some trim tables (most easily viewed as a graph) you can use to try and catch a drooping idle with load, one that does Ignition correction and one for fuel correction (these are for fine tuning though, not usually for "fixing"):
Ignition -->Advanced Ignition -->Ignition Trims --> Ignition vs. Idle Rpm:
This table allows you to control ignition advance relative to RPM and idle error
As you overshoot idle target (to the left) you can take away advance (retard) and bring idle back down or as you undershoot idle you can add ignition advance. The default setting is a nice smooth transition but you can ramp it up more steeply to catch a droop in idle.
The fuel trim works the same way (Fuel --> Advanced Fuel --> Fuel Trims --> Fuel offset vs. RPM).
You can add or take away fuel based on idle error and RPM.
Viewing/editing in the Graph is easiest as you can easily grasp what's happening with your changes and the idle error/RPM is shown real time.
This can be hours of entertainment :-)
wroark; I thank you for your suggestions
You sure know much more about the AEM than I.
Some comments in the same order:
1) I'll try the A/C 1 to 2 second delay advice as soon as I can connect my laptop to it.
2) Your comments on the odd timing values shows you sir know your ****!
I got my car dyno tuned with another calibration file but that one (along with most of the others I made) are in my other laptop which won't turn on and it's on its way to the repair shop to see if I can recover my data
. If I recover it, I'll be able to upload that file again and you'll see the difference. Since my car's engine was rebuilt less than 4 days ago I have the time to work with the AEM without risking my car (I can't take over 3,200 rpm for the next 1,000 kms and I get the feeling based on my work schedule that it's going to take more than 4 weeks to do it).
and finally (for now
), 3) I do have a wideband. My car idles at 14.7 to 15 if the A/C is off and at 11.5 to 12.1 the moment I turn the A/C on. I get the sense that I'm doing something wrong and the car goes way richer as soon as I turn the A/C on.
I'll follow your advice on the rest of your suggestions but I have no doubt that it will lead to me making additional stupid questions
Many thanks man; lots of work ahead for me.