Short update. My injector dead time wasn’t as high as I first thought, but decided to play with the settings anyway, glad I did.
Got the car to operating temperature (long drive). My warm idle was still mid 12’s. My dead time at CLT 194 degrees was set to .40m. I changed it to .35 and my AFR went to mid 14’s. I tried various numbers but seems it’s happy at .35
I also changed the rest of the table as well. Will keep a close eye on the logs going forward to ensure everything is good.
Boost controller and knock sensor also now configured and working. So more tuning to do.
Need MaxxECU base tune
Update:
Though my idle was stable at stand-still, I was having idle overshoot, general stumbling issues, and stalls. I could use the throttle to keep the engine from stalling and setting the idle, but kept thinking there had to be a better way. Heck, I didn’t have these issues with stock 30 year old computer. Which made me want to figure out what the stock ECU was doing for idle and deceleration. I remembered Rogue Tuning posted all that info.
Using the table on his site, I configured my MaxxECU to lock ignition using specific table. I plugged in the same values for timing and RPM, highest being 16 and lowest 4. Basically matching the stock timing table for idle. I lowered my regular timing table from 18 to 10. I set to close loop idle to use the idle timing table. I also adjusted my ICV PID values and played with the fuel overrun cut.
Long story short, I now have stock “like” idle with 14 AFR. But more importantly, idle returns normally to 850 RPM. No stalls and only two overshoots that I can see. It really does feel like a stock ECU. This was driving home in 90 degree heat with stop and go rush hour traffic and hills for about an hour.
Interestingly enough, the car “feels” very similar at 18 degrees advance idle to 4 degrees. Correct me if I’m wrong but I believe I’m saving fuel at 4 degrees?
I’m sure it could be adjusted more to perfect but I’m happy I’m now able to match stock feel to maybe 90%. I no longer have to baby the throttle. If I solve the couple of stumbles I’ll be at 100%, though that is more related to fuel overrun cut than idle settings (I think).
Going to make a few more adjustments and will then post my file. Should be good information for the next MaxxECU beginner.
Also note, I still have to tune using the Autotune feature. Car already feels best it’s ever has but I’m sure there is a lot more in it.
Though my idle was stable at stand-still, I was having idle overshoot, general stumbling issues, and stalls. I could use the throttle to keep the engine from stalling and setting the idle, but kept thinking there had to be a better way. Heck, I didn’t have these issues with stock 30 year old computer. Which made me want to figure out what the stock ECU was doing for idle and deceleration. I remembered Rogue Tuning posted all that info.
Using the table on his site, I configured my MaxxECU to lock ignition using specific table. I plugged in the same values for timing and RPM, highest being 16 and lowest 4. Basically matching the stock timing table for idle. I lowered my regular timing table from 18 to 10. I set to close loop idle to use the idle timing table. I also adjusted my ICV PID values and played with the fuel overrun cut.
Long story short, I now have stock “like” idle with 14 AFR. But more importantly, idle returns normally to 850 RPM. No stalls and only two overshoots that I can see. It really does feel like a stock ECU. This was driving home in 90 degree heat with stop and go rush hour traffic and hills for about an hour.
Interestingly enough, the car “feels” very similar at 18 degrees advance idle to 4 degrees. Correct me if I’m wrong but I believe I’m saving fuel at 4 degrees?
I’m sure it could be adjusted more to perfect but I’m happy I’m now able to match stock feel to maybe 90%. I no longer have to baby the throttle. If I solve the couple of stumbles I’ll be at 100%, though that is more related to fuel overrun cut than idle settings (I think).
Going to make a few more adjustments and will then post my file. Should be good information for the next MaxxECU beginner.
Also note, I still have to tune using the Autotune feature. Car already feels best it’s ever has but I’m sure there is a lot more in it.
Wanted to give a big thank you @BasHenneman .
I’m at VIR running novice class. The car feels really strong with the tune tweaks Bas made. Bas also fixed my wide band controller and settings. It seems to be working very well. I’m loving the MaxxECU. I don’t have the talent in the corners yet but I’m more than keeping up in the straights.
Have to give a shotout to Evergreen Turbo, running Raptor 27/6. With my ebc working well my boost feels great. I’m running out of talent to push anymore lol have to review logs but I don’t think I’m going past 1.75 bar and I’m hitting little over 100mph on the straights. But I can feel the turbo easily has more to give.
Looking forward to reviewing my logs.
Thanks again Bas.
I’m at VIR running novice class. The car feels really strong with the tune tweaks Bas made. Bas also fixed my wide band controller and settings. It seems to be working very well. I’m loving the MaxxECU. I don’t have the talent in the corners yet but I’m more than keeping up in the straights.
Have to give a shotout to Evergreen Turbo, running Raptor 27/6. With my ebc working well my boost feels great. I’m running out of talent to push anymore lol have to review logs but I don’t think I’m going past 1.75 bar and I’m hitting little over 100mph on the straights. But I can feel the turbo easily has more to give.
Looking forward to reviewing my logs.
Thanks again Bas.
Small update. As many amateur tuners would know, getting stock like idle can be frustrating.
I was simulating the stock ECU by locking ignition timing at idle and using the same values as stock (about 5 degrees BTDC at idle). My idle was at about 90%, as I mentioned earlier, of where I wanted it to be.
But I figured out how to let the MaxxECU handle both ICV and ignition. Coupled with my fuel pressure sensor being used to correct injector pulse width, my idle is now about 95% there. I’m hoping long term VE autotune or fuel learning will do the last 5%. Car feels really strong.
Also happy to see the oil pressure with the sensor I added. I used the sandwich plate with oil filter. It does report lower pressure than the dashboard gauge but still well within spec.
Next up is tweaking Realdash running on my android head unit and wired directly to the ECU over canbus. Realdash is awesome, highly recommended.
I was simulating the stock ECU by locking ignition timing at idle and using the same values as stock (about 5 degrees BTDC at idle). My idle was at about 90%, as I mentioned earlier, of where I wanted it to be.
But I figured out how to let the MaxxECU handle both ICV and ignition. Coupled with my fuel pressure sensor being used to correct injector pulse width, my idle is now about 95% there. I’m hoping long term VE autotune or fuel learning will do the last 5%. Car feels really strong.
Also happy to see the oil pressure with the sensor I added. I used the sandwich plate with oil filter. It does report lower pressure than the dashboard gauge but still well within spec.
Next up is tweaking Realdash running on my android head unit and wired directly to the ECU over canbus. Realdash is awesome, highly recommended.
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Tom
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It is my understanding from my TunerPro chip burning efforts that the factory DME does not lock in idle timing, but rather sets a base timing and then uses timing as a quick way to make minor rpm adjustments, creating a more stable idle that possible with the ISV alone. Or are you saying that's what you did to get to 95%?944m3 wrote: Tue Jan 06, 2026 9:45 pm Small update. As many amateur tuners would know, getting stock like idle can be frustrating.
I was simulating the stock ECU by locking ignition timing at idle and using the same values as stock (about 5 degrees BTDC at idle). My idle was at about 90%, as I mentioned earlier, of where I wanted it to be.
But I figured out how to let the MaxxECU handle both ICV and ignition. Coupled with my fuel pressure sensor being used to correct injector pulse width, my idle is now about 95% there. I’m hoping long term VE autotune or fuel learning will do the last 5%. Car feels really strong.
Also happy to see the oil pressure with the sensor I added. I used the sandwich plate with oil filter. It does report lower pressure than the dashboard gauge but still well within spec.
Next up is tweaking Realdash running on my android head unit and wired directly to the ECU over canbus. Realdash is awesome, highly recommended.
@johnb may be able to confirm (or debunk) my understanding and offer details on the factory strategy....
I was locking the timing at idle, which is what I thought the stock ECU does. But I could be completely wrong.
But now I have the standalone managing both air and timing during idle. For now that seems to be working a lot better. Perhaps that is what stock ECU was doing as well.
And just to define better, no occasional surges or stumbles. No occasional RPM slow drops or pauses before it settles to idle speed.
Though I do have a slight bit of hunting by maybe 50 RPMs if I sit in idle for a while. I’m thinking I need to tweak my PID settings to dial that out.
I will give respect to OEM tuners when it comes to idle tuning. Most stock cars will idle the same in the North Pole and the desert.
But now I have the standalone managing both air and timing during idle. For now that seems to be working a lot better. Perhaps that is what stock ECU was doing as well.
And just to define better, no occasional surges or stumbles. No occasional RPM slow drops or pauses before it settles to idle speed.
Though I do have a slight bit of hunting by maybe 50 RPMs if I sit in idle for a while. I’m thinking I need to tweak my PID settings to dial that out.
I will give respect to OEM tuners when it comes to idle tuning. Most stock cars will idle the same in the North Pole and the desert.
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Tom
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Right!?! And it's not just idle. With modern engine management systems, it's just expected for motors to run perfectly under every operation condition with a wide variety of fuels, cold starts, deep freeze, desert marathons, up hills, down hills, cruising, passing, WOT, etc. Pretty amazing really...944m3 wrote: Wed Jan 07, 2026 8:57 am
I will give respect to OEM tuners when it comes to idle tuning. Most stock cars will idle the same in the North Pole and the desert.
My turbo engine was very good after 20 hours of tuning.Tom wrote: Wed Jan 07, 2026 10:43 amRight!?! And it's not just idle. With modern engine management systems, it's just expected for motors to run perfectly under every operation condition with a wide variety of fuels, cold starts, deep freeze, desert marathons, up hills, down hills, cruising, passing, WOT, etc. Pretty amazing really...944m3 wrote: Wed Jan 07, 2026 8:57 am
I will give respect to OEM tuners when it comes to idle tuning. Most stock cars will idle the same in the North Pole and the desert.
No problems on cold starts, warm, mid and wot.
Wish I would have understood the current settings I’m using now, would have had similar experience as well haha But that’s ok, I’ve enjoyed the experience and learning. Have a better understanding of the “why’s”.ealoken wrote: Wed Jan 07, 2026 10:57 amMy turbo engine was very good after 20 hours of tuning.Tom wrote: Wed Jan 07, 2026 10:43 amRight!?! And it's not just idle. With modern engine management systems, it's just expected for motors to run perfectly under every operation condition with a wide variety of fuels, cold starts, deep freeze, desert marathons, up hills, down hills, cruising, passing, WOT, etc. Pretty amazing really...944m3 wrote: Wed Jan 07, 2026 8:57 am
I will give respect to OEM tuners when it comes to idle tuning. Most stock cars will idle the same in the North Pole and the desert.
No problems on cold starts, warm, mid and wot.
Are you leveraging a fuel pressure sensor? IIRC you are using a ECUMaster?
Had ecumaster classic on my old setup.944m3 wrote: Wed Jan 07, 2026 11:02 amWish I would have understood the current settings I’m using now, would have had similar experience as well haha But that’s ok, I’ve enjoyed the experience and learning. Have a better understanding of the “why’s”.ealoken wrote: Wed Jan 07, 2026 10:57 amMy turbo engine was very good after 20 hours of tuning.Tom wrote: Wed Jan 07, 2026 10:43 am
Right!?! And it's not just idle. With modern engine management systems, it's just expected for motors to run perfectly under every operation condition with a wide variety of fuels, cold starts, deep freeze, desert marathons, up hills, down hills, cruising, passing, WOT, etc. Pretty amazing really...
No problems on cold starts, warm, mid and wot.
Are you leveraging a fuel pressure sensor? IIRC you are using a ECUMaster?
Ecumaster Pro8 on my next.
Didn't have a fuel pressure, but I'm expanding my setup on my next setup.
Fuel pressure
Fuel temp
Dbw
Cop
IAT
Lamda
5x egt
Coolant temperature
Coolant pressure
Oil temperature
Oil pressure
Turbo speed
Boost pressure
The important about tuning, is to understand what a healthy window for the engine is, in different environments.
But road tuning above 400 bhp is scary
