Idle control strategy

[Reverant]

I'm currently using "Use last value" when re-entering CL.

The problem with this strategy is that once I cold-start the car and take off, I stop 5 minutes later and the idle is usually 1800-2000rpm and slowly coming down or not at all (overrun fuel cut oscillations).

So I tried "Use table". Better on this aspect, however "Use table" has droops when I add electrical loads during driving: While I drive, say I switch on the headlights or the cabin fan. On the next idle stop, the engine will droop, and recover. Next stop, same thing. And again, and again, and again, as the last position is not stored, to resume from there.

How about combining the best of both worlds? Ie "Use table" while the engine is cold, then switch to "Use last position"?

Thoughts?

Dimitris

[muythaibxr]

Are you using the voltage correction feature?

Most of the electrical loads you're talking about will pull voltage down, and that can be accounted for already.

Ken

[Reverant]

They don't pull down the voltage at all. The voltage is a flat 14.4V once the engine is running. The voltage will only drop if I apply so many loads that the alternator can't keep up.

[muythaibxr]

You're using the miata alt code right?

If you are, then I had another idea to help with that, but never documented the idea so I forgot about the problem.

Basically the idea was to figure out from how the bang-bang code was controlling the alternator what the load on the alternator was, and then adjust accordingly from that.

Ken

[Reverant]

You're using the miata alt code right?

If you are, then I had another idea to help with that, but never documented the idea so I forgot about the problem.

Basically the idea was to figure out from how the bang-bang code was controlling the alternator what the load on the alternator was, and then adjust accordingly from that.

Ken

Yeah, that would help immensly. I can easily test the code if need be.

[PDX5]

What about those who don't have a miata? I have the same issue and have been the using initial value table with okay results. Adaptive advance helps greatly. Still, a temperature switch point would be nice.

[muythaibxr]

If you have an alt that is MS controlled we can factor that in. If not, use voltage correction. I doubt your alt reacts as fast as the miata one.