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ECMlink Tune Related Idle Surge HELP

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bryanzomg

Proven Member
176
20
May 18, 2015
melrose park, Illinois
Mod list is updated. Base timing verified, mechanical timing verified, BLT all good. ISC has been tested, TPS is properly adjusted.
I recently upgraded fuel pump to a walbro 350, added AFPR set at 38psi base, bigger turbo, and 2150cc injectors. I am getting horrible idle surge, it seems once I go into closed loop mode. I must add AEM wideband on link is a bit off, in reality its a bit richer. Can someone look at my tune i am willing to pay.
I am running e85, all i need is an idle tune I want to get rid of idle surge.
I've provided a cold start log and another log after messing with fastidleisc settings

I must add, I have global set up that way because it runs really rich when starting, I have been able to get idle surge to STOP when lowering base fuel pressure to under 20psi or so but that doesn't seem right
 

Attachments

  • cold start idle surge.elg
    100.5 KB · Views: 20
  • adjustment isc.elg
    65.8 KB · Views: 22
Your Idle switch is not functioning. It sits at "0" even though your throttle position is zero. Try "simulating" it in the RPM/TPS tab. The motor doesn't know that you are at idle currently. I would run 43.5 lbs fuel pressure (as that is what most injectors are tested at) and the global of -80% will be too much, see what the engine likes at around -68 to -70%. You can always go back. My setup is similar, with 2150s, HX40, 525 pump and my global is around the -69% area. I am using negative dead time also, which you may need to play with. Just some things I see on a quick glance this morning.
 
Your Idle switch is not functioning. It sits at "0" even though your throttle position is zero. Try "simulating" it in the RPM/TPS tab. The motor doesn't know that you are at idle currently. I would run 43.5 lbs fuel pressure (as that is what most injectors are tested at) and the global of -80% will be too much, see what the engine likes at around -68 to -70%. You can always go back. My setup is similar, with 2150s, HX40, 525 pump and my global is around the -69% area. I am using negative dead time also, which you may need to play with. Just some things I see on a quick glance this morning.
Will do on the idle switch, I believe I simulated it on the other log, no difference
 
Your O2 isn't cycling like it should and is probably because it is lean. Your STFT's are adding 16% more fuel when it displays so I would move my global back to the -70's. That may get you cycling and get those fuel trims to within + - 5%.
Are we running gasoline or E85 and speed density or MAF?
 
Your O2 isn't cycling like it should and is probably because it is lean. Your STFT's are adding 16% more fuel when it displays so I would move my global back to the -70's. That may get you cycling and get those fuel trims to within + - 5%.
Are we running gasoline or E85 and speed density or MAF?
I stated above but I am running e85 on speed density. Doesn’t it have to reach a certain coolant temp as well to start cycling? I will change settings today and base fuel and see how it goes
 
For closed loop operation the temp has to be 180+ IIRC. E85 will require you to run about 30% more fuel. My car is also an E85 car. My car starts right up, idles on its own and starts on first try (well, maybe I have to hit the key a 2nd time). I tune the idle to stoich for gas (14.7) on my wideband and then watch my Long and Short term fuel trims and adjust them both to with in 5% of zero.
Here is a log from her. Maybe some of it will be of help to you or maybe none of it.
Marty
 

Attachments

  • log.2022.04.27-02 Warm up log for Gary and BROKEN OUTPUT SHAFT (1).elg
    266.5 KB · Views: 15
Quick first thoughts, why doesn't your IPS work?
Why do you have the min injector pulse width set to 2000us?
If you are going to use IntBatteryAdj why are you also using Global Deadtime?
Honestly I just copied someone else’s setting on here from forums to start somewhere, I’ll revert the injbatteryadj back towards stock values
IPS must be loose, I reinstalled a new working TPS since my last one would randomly throw TPS cel 0014
 
Enable the "Simulate Idle Switch from TPS"
 
I'm sure that you got your initial settings by trying the fuel calculator but it wasn't compensated for ethanol use (9.5 stoich). I did a screenshot of your current settings and what it would suggest if you plugged in all of the correct factors (2nd screenshot). You may already know what these mean, but just in case you were not sure, I made a explanatory picture. You should zero out that deadtime, although it may need to be tweaked just a little one way or another to get "dialed" in.
I apologize if you already have this knowledge.

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Enable the "Simulate Idle Switch from TPS"

He did in the second log but you know how I feel about simulating it.

I think much of the surging is caused by having the min pulse width set. That's there I believe to assist with the run of questionable injectors that behave so badly with short IPW's but which these injectors it's way too long for a good idle. The IPW never changes and you see the RPS surge up and down with the ECU varying the timing advance.
 
Yeah I do. I go with Brett on TPS adjustments. Adjust it manually which is why I put allen head screws in so it makes it easier to loosen the TPS and make those adjustments. :)
My Pulse widths are at 840, which I assume is the initial value for that, as I have never changed it.
I can spot the little things and I am glad that YOU can spot the bigger things!!! :thumb:
Thanks Steve!
 
Hey guys you've been so helpful. Here is a log with updated settings.
I'm trying to get IPS to read on link without simulating. Resistance is good between the connector on TPS side. (it's a 90),
Is it possible IPS isnt adjusted correctly therefore not reading on ecmlink. I do have a ground for throttle body to firewall
As you can see it'll begin to surge and stall out
 

Attachments

  • updated settings.elg
    46.4 KB · Views: 38
It only went into closed loop once in that log when the coolant temp was > 86F around 64 seconds in.

I'm trying to figure out why the timing starts stuttering and the battery voltage drops along with the engine vacuum and the WB maxes out lean but the injector PW actually gets shorter, then the WB wakes up and almost matches the ECU's target AFR.
 
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