spark scatter control and min+max pw

How are u guys tuning for spark scatter, iv looked up alot of things but really haven't found crazy amounts on this. I cant even seem to disable it to try to tune the fuel at idle, Idle is what im tuning for. Iv saw where it says to disable IDLTMP and SSTEMP but i do not have either of them in my cal, or any other cal i open. My next question is i have my min and max pw for my injectors that id like to apply into the cal is this possible? If your curious to as of what injectors i have https://www.rcfuelinjection.com/Stor...-hold-injector. I updated the battery offset to the latency chart for these injectors and i believe it to be correct. Car just dose not like to cold idle very well, I do not believe this to be the injectors fault, since it was doing this before these injectors but now its alittle richer at idle. Also has a random like miss or so out of boost randomly. Any help or advice is much appreciated.

Anyone lol?

Could the random miss be attributed to the baro solenoid opening every so often to update the atmospheric pressure reading? I've never had to mess with any of the spark scatter stuff at all to get a good idle.

what year ecu are you using?

sstemp is TempAboveWhichSparkScatterIsActive and is in the scatter control section on a 89 smec turbonator cal.
idltmp is IDLADD AboveThisTemp and is in the same group.

id adjust the pumping efficiency at your idle RPM and see how that effects the idle.

pumping efficiency is what you want to tune for first after scaling for injectors.

did you also watch your fuel pressure? if you have a large pump, the return line may be to small to bleed off the excess especially because your injectors are so large so the idle pulsewidth is going to be so small.

Brian

If fueling is good while driving but rich at idle, adjust the fuel baseline table.

Thanks for all the replies guys, 87 lm using ostrich. I got the pump eff table pretty good, afrs are perfect in boost and part throttle. I just set the pump eff then modified Wot fuel and Pt fuel to get the afrs where i wanted them. I think the car idles poopy because of everything before ported and way more efficient than factory, but like no matter what i adjust i cant seem to get it right. The missfire is random just getting off the throttle it'll drop vacuum and go lean for like a split second then its fine, dose not do it in throttle at all. The idle is fine for like 10seconds on startup then it goes does its random vacuum drop and goes lean till im guessing the 02 feedback fixes it then it idles normal again for a few seconds. Also if i rev the car at all it idles down real low and trys to get back up to the 1k idle rpm or it just stalls out. Just makes things rather annoying, driving the car it runs fine. Also Rob the Fuelbaselinefrommap is already on the lowest spot for the vacuum i need to adjust for just from the boostbuttons cal default. 14.7s where i would want to adjust correct? Thanks

yeah 14.7 is good for idle. When it's cold it doesn't use the O2 feedback. Are you sure the speed sensor is working? That can cause issues like you have also. You can also try dropping the PE table down at your desired idle rpm and see what that does. Ported heads sometimes act less efficient at idle and low revs. But if it's fine driving around in gear at 1200 to 1500, PE should be pretty close. You can add timing at idle as well, using the AdvancefromRPM table.

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Originally Posted by cbw1994

Car just dose not like to cold idle very well,

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What a/f are your cold idle?

Cold idle is decent like 12.5 to 13 then itll stay at 14.7 for awhile till the 02s start kicking it i guess, then it will do its vacuum drop go lean and try to go back to 14.7 and then try to stall out. fulled warmed up its a little rich at like 12.5. would love to get it to 14.7. If it idled smooth id be fine with whatever at this point. Iv tried dropping the pump efficiency down at idle rpms, but unless i drop it alot it really has no crazy effect, the stalling and weird lean to rich spots are whats really annoying because once it goes lean and go back to richish the idle speed drops and wants to stall out. The vss does work.

Upload your tune so we can take a look.

In megasquirt, we can disable o2 feedback while tuning a/f.

https://filebin.net/q8o8m99dyli9bf3f
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See if that works please only way i could figure out how to post

You ever get a chance to take a look at my tune tryingbe?