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ignition angle issue


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Hello I have a Jeep 4.0 based engine bored and stroked on a storm x ecu running factory jeep trigger pattern with jeep 2000 selected and factory triggers (hall effect). Running sequential on modeled equation, ls coils, bosch 312cc injectors, mustang throttle body and iac. Have had the car running now for a bit going back and forth with my tuner sending logs and getting revisions. Finally got to the point I could drive it to work and lay into it for some good data. Everything has been great and good power. Now when I start it it will run great for 15 to 45 seconds then the ignition angle gauge in the tuning screen starts fluctuating badly, I have tried 3 different new crank sensors with the same result. Car ran great for 3 days with no issue and nothing has changed since then. Factory shielded link wires to both triggers with no damage, continuity between trigger plug and ecu header connector for sensor ground and signal. Have verified steady 5v to the triggers even when ignition angle is being eratic, have also tried all different air gaps on the crank sensor with same results. Attatched is a log, a trigger scope, and my tune. Any help would be appreciated cheers - Jimmy

PC Datalog - 2022-06-18 12;27;49 pm.zip TriggerScopeLog9.zip spirit jimmy dean new (4).pclx

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This is idle ignition control and is normal to bounce around a lot at idle.    Ignition timing can increase and decrease torque much quicker than the idle valve can so you want the ign timing to do the majority of the instantaneous correction and the idle valve looks after the longer term error.  Yours is bouncing a bit more violently than typical since your proportional gain is very high.

Set your idle ign proportional gain to 1.0 and the derivative to 0.0 would typically be about all you need.  If you go too high with proportional you will feel the idle get rough.

4 hours ago, supra11487 said:

Now when I start it it will run great for 15 to 45 seconds then the ignition angle gauge in the tuning screen starts fluctuating badly

This is because during the start up hold and decay (you have each set to 10seconds, idle ign is disabled and the ign is held static at the idle ign target.  The hold and decay of a couple of seconds each is normally all that is needed.


Does your idle valve actually work?  Doesnt really look like it is in the log.  As a test with ign on, engine not running, put aux 5 in test mode and set frequency to 10Hz to see if you can hear it clicking.

Change the settings in orange below will likely give you a better starting point.



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Once again thank you Adamw. Changed those settings and it seems much happier now at least at idle. Yes iac does work, will have to send logs back to the guy I have tuning the car to smooth some things out im sure. This is a log from after making those changes.

PC Datalog - 2022-06-16 7;29;32 pm.zip

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7 hours ago, supra11487 said:

It will only let me send tiny logs for some reason. I can only go 16.2kb now and have no logs that small

Each forum member gets a small upload allowance when they join to make it easy to get started.  Once you have used up that allowance you can use something like Google drive, Onedrive, dropbox, wetransfer or similar to share your files.  

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Yep, looking better now.  The idle base position table needs a bit of work now.  To do this log a cold start and keep logging untill fully warm, then look back at what idle position was required for each temperature and use that to update your base position table.  You only have 40-50°C in that log above.  But start with something like below will be much closer:


I would increase the idle integral gain to 0.5 also.  

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