Microsquirt noob needs some tuning advice

Hi everyone, hope you all had a great Christmas! So I'm relatively new to tuning and have gotten my car to the point where it will start and idle ok. The main problem I'm having is dialing in my warm-up idle. At first, it would oscillate so bad when first started cold, that it would need to be restarted 4 or 5 times before it would stay running, at which point it would oscillate pretty bad. Once it was fully warm, it wouldn't oscillate as much, but it would still be there. I played with a combination of adjusting the VE table and spark table until it didn't really oscillate that much. Then I adjusted the WUE and PWM idle warm up and that fixed the bad oscillation during cold start, but it idles pretty darn high until it starts warming up and then gradually falls to around where I want it to idle. Looking at my logs, it looks like my timing is pretty high when its cold, so I was thinking that I may want to retard the timing through the Cold Advance, until it started warming to, to help bring the idle down. Just wanted to see it that makes sense and/or if someone could look at my tune and log to see if anything jumps out or looks grossly wrong. Anyway, I appreciate any help you can give. Hopefully all the info you need on my car is in my sig, but please let me know if you need anything else.


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Well your going to have to start over after some changes.
under general settings you need to set it to "incorporate AFR" otherwise the AFR and VE tables are separate and not tied together. This makes things wonky at end game tuning.
Your using "holes" in the IGN table to stabilize the idle speed, this can work but its not a first choice. and likely where some of your oscillation is coming from. You do need to use timing to control idle speed but we want it to work "better" ; I suggest using the idle advance feature at the bottom of the startup settings page.
You should be running the idle valve at 313HZ [under idle control] at this HZ the valve will be full closed at 30% and full open at 70% or so. Knowing these numbers will help you get the idle speed dialed in.
I usually run everything in closed loop mode but warm up [open loop] works just fine if setup properly.
FWIW the E303 cam is going to want between 14 and 22* at idle and tip in timing it likes more timing [around 22ish] your ign table is not a bad starting point in this regard.
Thank you so much for taking the time to look at it! I have a couple questions:
1) What do you mean regarding "using holes" in the ignition table? Are you referring to how I've sort of boxed the idle in with the values on the spark table so it doesn't oscillate, or is there a setting I mistakenly have on that is for using "holes"?
2) For the idle advance setting, what would you recommend using (Load, RPM or Adaptive)?
3) For the Idle valve frequency, should I select 313hz and then jog the idle valve up and down to find the limits and put them back into the closed loop idle settings for when I'm finished getting it to idle well and switch back over to closed loop idle?

My plan is to use open loop mode to dial in the warm-up idle and up to temp idle, then switch back to closed loop mode to finish it off. It'll probably be a few days before I can implement everything with work and house guests, but I'll report back soon! Thanks again for your assistance!!

Well, I got a chance to play with the tune a little. Got it idling alright with ego contl off and the spark table fixed in open loop mode. Getting something weird happening when I switch over from fixed timing to using the spark table. For some reason the my spark keeps shooting up to around 30 or so degrees causing the idle to jump up with it. Also, it does this weird thing now when I turn off the car and then start it right back up (after it's fully warm). It idles like crap for 30 sec or so, or just dies and I have to keep restarting it. Then it will eventually run normal again. I appreciate any help!


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I went back and fooled with it some more. Seems like the idle advance was creating some problems (or it was my inability to set it up correctly). It will idle alright with the EGO control and idle advance on, but it idles better with both of them off (in closed loop mode). I tried different settings for the idle advance, but it didn't seem to like anything I did. I logged the idle with ego cntrl and idle advance both off, with both on and with just idle advance on. I also tried to play around with the PDI settings, but didn't have much luck. Guess I'll just keep plugging away at it.


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