Can't get dashpot adder to work
 

Short story: I get a bit of idle drop when entering idle. Occasionally it's pretty bad and it almost stalls. Once CL idle kicks in, it's fine. I checked the logs and the dashpot adder didn't seem to do anything. I raised it from around 3 to 10% to make sure it would be noticeable - still nothing. I got some input from Reverant and tried setting the Min duty for PID to around 20, close delay to 0. Still nothing (see log).

https://www.miataturbo.net/attachmen...ine=1353168696

https://www.miataturbo.net/attachmen...ine=1353168696

Any ideas on what else I could try?

Thanks,
- Tom

Still trying to fix this but without any luck. Any input appreciated!

- Tom

Your idle valve barely moves at all. it pretty much stays locked at 35.5% I think you have way too much I value.

But if anything, the valve should drop down to 25% when youre driving regardless, I think this might be an issue with the firmware.

Does the "Trans Eng" indicator ever change state when you change gears?

If I recall correctly, it used to sit around 26% before I did this:
I don't know if that makes more or less sense to anyone (I'm probably in the latter category :))...

I'll have to check. I don't have my tuning laptop with me at the moment. I'll report back.

- Tom

changing the min duty for PID would not keep the idle valve locked at 35-36% throughout your entire log file.

If anything, it should be sitting at 20%PWM now...

It's green when idling and between gears. Red while driving.

Forget about the high Idle PWM%. I forgot that I also had tried closing the idle adjustment screw (or whatever it's name is) when troubleshooting. Sorry for the confusion.

- Tom

regardless of how low you adjusted the idle screw, it should still be manipulating your PWN% to compensate.

It does compensate with higher Idle PWM% when for example I turn on the high beam, the rear window heater etc. It also idles fine. Only idle problem is the missing dashpot adder, resulting in an idle dip when coming off the throttle and engaging the clutch.

What are the conditions for a "known good Idle"? I'm wondering if it doesn't acknowledge my idle as "good" and therefore doesn't apply the dashpot adder.

- Tom

Your log showed a non functioning idle value; as far as i can tell, it's not working at all. It doesn't close when on the throttle, it doesn't add dashpot when you lift, it doesn't react to PID, it doesn't do jack shit but sit there at 35% PWM. Does that makes sense?

Without seeing a log that shows the idle value actually doing something, I have to assume there's a bigger issue than just "no dashpot," because as far as I see it, you have no idle code.

First of all, it doesn't close because the close delay is set to 0 as stated in the very first post. Before I did this, it closed fine but opened up at the same value as it closed from. It does move between 33 to 36 across the log I attached. I can get you other logs with more stuff going on if you prefer - In fact, if there's anything specific you'd like me to log, let me know.

- Tom

oh. i missed that :)

let me look at the log again when I'm back home.

I lowered the P% and I% by a fifth to make sure the Idle RPM and PWM% would be stable, then did another log (attached along with the .msq).

No luck.

The idle dip is worst when down-shifting before engaging the clutch (621 RPM at 1059.4s).

Strange thing going on at 830s - 832s and again at 1005s - 1015s. The Idle PWM% drops to 19.9 (= Min. Duty for PID). It doesn't have an effect as it didn't happen during idle - just thought it was curious.

I turned on the heater fan and rear window heater at the end of the log and the PWM% went up by 6 points to deal with it.

- Tom