Notices
MEGAsquirt A place to collectively sort out this megasquirt gizmo

My OWN thread about my OWN MS3x idle "issue"

Thread Tools
 
Search this Thread
 
Old Dec 19, 2013 | 07:41 PM
  #1  
poobs's Avatar
Thread Starter
Senior Member
iTrader: (1)
 
Joined: Apr 2008
Posts: 810
Total Cats: -6
From: Florida
Default My OWN thread about my OWN MS3x idle "issue"

Originally Posted by hornetball
+1 on Ben's analysis. In this area, your spark advance is operating off your spark map. Make sure the bins in your spark map around this area are all about the same. What's happening is that spark is advancing which produces more torque and increases RPM. Your idle duty then responds to that (with lag). As the RPM decays, the reverse happens. Bottom line, you've got a negative feedback loop. Post your spark map. Should be obvious.

Thank you, thank you, thank you.

Now I'm not 100% sure but I think the MS3 has a separate idle timing or is that just a separate idle VE (?)

This idle dip has been driving me crazy - tried every closed loop setting imaginable

Last edited by poobs; Dec 19, 2013 at 07:41 PM. Reason: typo
Old Dec 19, 2013 | 09:41 PM
  #2  
poobs's Avatar
Thread Starter
Senior Member
iTrader: (1)
 
Joined: Apr 2008
Posts: 810
Total Cats: -6
From: Florida
Thumbs up

Originally Posted by DNMakinson
MS3 has separate Idle VE and Idle Advance, if desired. There is additionally an "Idle RPM Timing Correction" that can be turned on in the same place as Idle Advance. I have never used that, but I will try it tomorrow.
Thanks so... much
Please let me know what you guys find. I will do the same.
Old Dec 19, 2013 | 10:07 PM
  #3  
poobs's Avatar
Thread Starter
Senior Member
iTrader: (1)
 
Joined: Apr 2008
Posts: 810
Total Cats: -6
From: Florida
Default

Do you guys think that these may have something to do with the issue ...

Under Start Up and Idle

Idle RPM Timing Correction Curve – RPM vs timing delta ?

Idle Advance Settings - Turns Idle Advance on/off & shows timing advance vs load
Sorry abuot the screen shots.

First time that I look at these so any clarification will be greatly appreciated
Attached Thumbnails My OWN thread about my OWN MS3x idle "issue"-idle-advance.jpg   My OWN thread about my OWN MS3x idle "issue"-idle-rpm-timing-correction-curve.jpg  
Old Dec 20, 2013 | 08:00 AM
  #4  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

poobs, turn idle advance off.

If you're having an rpm dip coming to idle, it could be a plethora of things. I can seriously think of about 5-6 things it could be.

start your own thread, explain the issue fully, and post datalogs and your msq exactly like Richy has done in his first post here. then we can deal with YOUR issue instead of piggybacking off another's.
Old Dec 20, 2013 | 08:49 AM
  #5  
poobs's Avatar
Thread Starter
Senior Member
iTrader: (1)
 
Joined: Apr 2008
Posts: 810
Total Cats: -6
From: Florida
Thumbs up

Originally Posted by Braineack
poobs, turn idle advance off.

If you're having an rpm dip coming to idle, it could be a plethora of things. I can seriously think of about 5-6 things it could be.

start your own thread, explain the issue fully, and post datalogs and your msq exactly like Richy has done in his first post here. then we can deal with YOUR issue instead of piggybacking off another's.
Thanks man !!! I really appreciate the suggestion. I'll start a thread but please check your PM when you get a chance.
Old Dec 20, 2013 | 11:59 AM
  #6  
hornetball's Avatar
Elite Member
iTrader: (4)
 
Joined: Mar 2008
Posts: 6,301
Total Cats: 697
From: Granbury, TX
Default

Well, no matter what is controlling spark advance in the idle region, it helps to keep the advance stable so that PW to the idle control valve is the only thing affecting RPM. The only exception to this might be a spark bump at the extreme low end to keep the engine from bogging.

KISS or die.
Old Dec 20, 2013 | 12:04 PM
  #7  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

His MS3x was setup to use adaptive timing control to control the idle.

Locking timing at idle is SKIS: simply keeping it stupid.
Old Dec 20, 2013 | 12:08 PM
  #8  
hornetball's Avatar
Elite Member
iTrader: (4)
 
Joined: Mar 2008
Posts: 6,301
Total Cats: 697
From: Granbury, TX
Default

Whatever. His idle is much less stable than mine. Mines like stock, even with AC. C'ya.
Old Dec 20, 2013 | 12:15 PM
  #9  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

well it's not tuned.

mine was better than stock, even with a/c, headlights, and a subwoofer booming.

adaptive timing is really amazing. the PID code gets the idle valve close, then the MS controls the timing to keep it on target instead of manipulating the idle valve. It's much improved and locking the timing negates this feature.
Old Dec 20, 2013 | 01:52 PM
  #10  
poobs's Avatar
Thread Starter
Senior Member
iTrader: (1)
 
Joined: Apr 2008
Posts: 810
Total Cats: -6
From: Florida
Thumbs up

Brain

My tune is based on yours. My current spark table increases timing right away so it lacks the low timing value area that you guys mention - I still have to modify it
Far as I know timing advance at idle is turned "on" as is the Idle RPM correction (on the same screen )

What do you guys mean by locked on ?

Should I disable it ?


Thanks guys
Old Dec 20, 2013 | 02:34 PM
  #11  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

under idle advance setting, turn OFF timing advance. leave RPM timing ON.
Old Dec 20, 2013 | 02:43 PM
  #12  
poobs's Avatar
Thread Starter
Senior Member
iTrader: (1)
 
Joined: Apr 2008
Posts: 810
Total Cats: -6
From: Florida
Default

Originally Posted by Braineack
under idle advance setting, turn OFF timing advance. leave RPM timing ON.
Did that & went for a drive round the block
As I turned the corner the idle dipped when I stepped on the clutch ala MS1 sad2:
Old Dec 20, 2013 | 02:44 PM
  #13  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

like I said, could be anything.

need datalogs, info, msq, etc etc etc.

disabling the timing advance wasn't the cause, and i never expected it to be a fix.
Old Dec 20, 2013 | 02:48 PM
  #14  
poobs's Avatar
Thread Starter
Senior Member
iTrader: (1)
 
Joined: Apr 2008
Posts: 810
Total Cats: -6
From: Florida
Default

Thanks man!!!

This is the tune I'm running
Logs are on the way
Attached Files
Old Dec 20, 2013 | 02:59 PM
  #15  
poobs's Avatar
Thread Starter
Senior Member
iTrader: (1)
 
Joined: Apr 2008
Posts: 810
Total Cats: -6
From: Florida
Default

Heres a log
Just driving around sedately

It did not do anything drastic but feels clunky between shifts and a slight surge on light acceleration.
Feels clumsy ..

Any insight is better than nothing thanks again
Attached Files
Old Dec 20, 2013 | 03:25 PM
  #16  
poobs's Avatar
Thread Starter
Senior Member
iTrader: (1)
 
Joined: Apr 2008
Posts: 810
Total Cats: -6
From: Florida
Default

Here's some food for thought.

When I tap the gas pedal - no load from idle- it returns to idle very well but when I put a load on the motor the fun begins.

So it would seem that depending on what the motor is doing load wise when I step on the clutch it will recover nicely or dip.

What setting controls the above ?
Old Dec 20, 2013 | 07:10 PM
  #17  
poobs's Avatar
Thread Starter
Senior Member
iTrader: (1)
 
Joined: Apr 2008
Posts: 810
Total Cats: -6
From: Florida
Default

Hey!!! ?? Where did not nobody go ?
Reply
Leave a poscat -1 Leave a negcat
Old Dec 21, 2013 | 06:05 AM
  #18  
richyvrlimited's Avatar
Elite Member
iTrader: (1)
 
Joined: Jun 2006
Posts: 2,642
Total Cats: 42
From: Warrington/Birmingham
Default

Originally Posted by poobs
Hey!!! ?? Where did not nobody go ?
It's not even been 24 hours, people aren't here waiting for you to post you know.
Old Dec 21, 2013 | 09:52 AM
  #19  
Braineack's Avatar
Boost Czar
iTrader: (62)
 
Joined: May 2005
Posts: 80,552
Total Cats: 4,368
From: Chantilly, VA
Default

Originally Posted by poobs
Heres a log
Just driving around sedately

It did not do anything drastic but feels clunky between shifts and a slight surge on light acceleration.
Feels clumsy ..

Any insight is better than nothing thanks again

did you want help with a idle dip issue or an acceleration enrichments tuning issue?
Old Dec 21, 2013 | 09:58 AM
  #20  
poobs's Avatar
Thread Starter
Senior Member
iTrader: (1)
 
Joined: Apr 2008
Posts: 810
Total Cats: -6
From: Florida
Default

Originally Posted by Braineack
did you want help with a idle dip issue or an acceleration enrichments tuning issue?
It would be great to get both issues sorted out.

I'd say they might be related.



All times are GMT -4. The time now is 12:03 AM.