8 Dec 2017

The little fire turned into a beast which is still completely uncontained; a couple coworkers are waiting to see if their homes are still standing. Last night our pond skimmer worked overtime collecting tree debris. Imagine that as burning embers driven by 30-80mph winds.

In car news, it’s fairly straightforward tuning a fuel and ignition map, what’s not is cold-start and idle. It takes a lot more time because it’s so subjective, plus cold-start can only be worked on for a few minutes before the car has to cool off.

AEM’s ECU versatility allows changing many parameters, some by a lot. For example, the idle PID control loop terms appear as “X.XXX”. Annoyingly, they don’t give a rough idea where to start, instead sticking with “every engine will be different.” Well, yes, and no. For example, is a good starting point 9.000, 1.000, 0.456, 0.045, or 0.005? If you start with 0.005 when the majority of engines need 1.000, it wastes time. It’s like being asked to guess a number between 1 and 10,000 without even a ballpark starting point, or even the state where the ballpark is located…

I bring this up because idle is currently running an “I” term of 0.010. Today I found a post where someone got AEM to reluctantly cough up a starting point. The response was “… cars with aggressive setups and big injectors may need a ‘P’ term of zero and an ‘I’ gain of 0.1-0.2 at idle to prevent oscillation.” So, maybe what I thought was okay could stand further improvement. Increasing “I” to 0.05 didn’t show a marked improvement, but it needs to be driven, but now it’s time to pick up the wife at LAX. Told the neighbors that if things get insane around here before we’re back, to rescue our dog.