Idle Help - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


MEGAsquirt A place to collectively sort out this megasquirt gizmo

Reply
 
 
 
LinkBack Thread Tools
Old 05-15-2012, 01:58 PM   #1
Junior Member
Thread Starter
 
Join Date: Oct 2009
Location: Anderson, SC
Posts: 321
Total Cats: -2
Default Idle Help

So I don't know if I'm missing something but I think I have my charging system finally working but my idle won't stay stable and the car stalls with good afr's. If I keep it really rich it'll run though. Do I have something mixed up?
Attached Files
File Type: msl 2012-05-15_11.41.39.msl (240.5 KB, 102 views)
File Type: msq CurrentTune.msq (78.9 KB, 72 views)
cowboys647 is offline   Reply With Quote
Old 05-15-2012, 03:40 PM   #2
Elite Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,010
Total Cats: 583
Default

Look here starting around post #11 for a decent idle tuning procedure:

https://www.miataturbo.net/megasquirt-18/timing-idle-requesting-some-help-57133/
hornetball is offline   Reply With Quote
Old 05-15-2012, 04:51 PM   #3
Junior Member
Thread Starter
 
Join Date: Oct 2009
Location: Anderson, SC
Posts: 321
Total Cats: -2
Default

On 1a you say change the minimum and maximum duty cycle to 19. Do you mean in the pwm idle duty cycle in the right column? My kpa is solid at 30 and my rpm is set nicely at 950. The only problem is I can't get a solid Africa. If I keep it at 12.5 or less its perfectly smooth but any more and it just gets real rough?
cowboys647 is offline   Reply With Quote
Old 05-15-2012, 07:00 PM   #4
Elite Member
iTrader: (3)
 
Join Date: Mar 2008
Location: Granbury, TX
Posts: 6,010
Total Cats: 583
Default

That procedure was specifically for an MS-1 and an older 1.6. The concepts are applicable to what your are doing although your idle duty cycles should be much lower. The point of the procedure is to remove variability so that you setup one item at a time. A fixed duty cycle (pwm idle duty cycle) allows you to set your VE for maximum vacuum without interference from a variable air leak.

For idle, it really is better to set your fuel with vacuum than to target an arbitrary AFR. If you want to target AFR then: 1. Make sure your AFR gauge is accurate; and 2. Slightly richer than stoichiometric is what you shoot for (something like 12.5 to 13.5:1).

Looking at your log file, it doesn't look like your AFR signal is reliable. I see excursions up to around 20:1 with all other parameters looking pretty normal. This can't be real. One thing to consider is whether the sensor's heater element is functioning correctly. At idle, supplemental heat is usually required to get a good reading out of these things. You might also look for wiring/grounding issues.
hornetball is offline   Reply With Quote
Old 05-15-2012, 08:59 PM   #5
Junior Member
Thread Starter
 
Join Date: Oct 2009
Location: Anderson, SC
Posts: 321
Total Cats: -2
Default

Oh ok I gotcha. It seems like it works right but then again I don't have anything to compare it to. Thanks for the help
cowboys647 is offline   Reply With Quote
Old 05-16-2012, 12:56 AM   #6
I'm Miserable!
 
Join Date: Jun 2009
Location: albany, ga
Posts: 1,869
Total Cats: 3
Default

what fuel injectors?
Techsalvager is offline   Reply With Quote
Old 05-16-2012, 11:39 AM   #7
Junior Member
Thread Starter
 
Join Date: Oct 2009
Location: Anderson, SC
Posts: 321
Total Cats: -2
Default

rx7 460's
cowboys647 is offline   Reply With Quote
Old 05-16-2012, 07:14 PM   #8
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,900
Total Cats: 1,792
Default

Post log. Id reccomend the latest gslender firmware. Tuning idle iis easy but takes a few mminute worth of time invesment to tune the parameteres correctly
Braineack is offline   Reply With Quote
Old 05-16-2012, 07:44 PM   #9
Junior Member
 
Join Date: Feb 2007
Location: 11368 miles from where i would like to be
Posts: 269
Total Cats: 92
Default

If your charging system has affected your idle significantly, I'd look to your injector dead time settings, they're likely wrong.
rb26dett is offline   Reply With Quote
Old 05-16-2012, 07:45 PM   #10
Junior Member
 
Join Date: Feb 2007
Location: 11368 miles from where i would like to be
Posts: 269
Total Cats: 92
Default

Though, having said that, it's actually *not* possible to have them correct in MS2 (or ms1), however you can get close enough for it to be ok most of the time.
rb26dett is offline   Reply With Quote
Old 05-16-2012, 09:23 PM   #11
Junior Member
Thread Starter
 
Join Date: Oct 2009
Location: Anderson, SC
Posts: 321
Total Cats: -2
Default

I've never messed with my dead times actually. Guessed I missed those. Its weird at idle it surges a lot and starts slowly going lean until it dies. Not sure if its charging related or what not. Ve table is steady throughout idle area, timing is good, and afr's start out good. I had a dyno appointment the other day at begi but for some reason my car stopped charging. Now that it is running (poorly) I may try and limp it down there so they can do their magic.
cowboys647 is offline   Reply With Quote
Old 05-16-2012, 09:39 PM   #12
I'm Miserable!
 
Join Date: Jun 2009
Location: albany, ga
Posts: 1,869
Total Cats: 3
Default

need a log of when it happens, a long log.
Techsalvager is offline   Reply With Quote
Old 05-16-2012, 10:29 PM   #13
Junior Member
Thread Starter
 
Join Date: Oct 2009
Location: Anderson, SC
Posts: 321
Total Cats: -2
Default

Just went out to get a log and I think somethings draining my battery while the car is off. I fully charged it last night...
cowboys647 is offline   Reply With Quote
Old 05-17-2012, 06:14 PM   #14
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,900
Total Cats: 1,792
Default

What does the battery voltage on your above log look like? Should be solid around 14.2v
Braineack is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Back to Stock Part Out!! Turbo Parts, MS2 Enhanced 01-05, Suspension, and MOAR! StratoBlue1109 Miata parts for sale/trade 16 10-02-2015 10:39 AM
Time to start learning and play with tuning The Gleas MEGAsquirt 3 10-01-2015 10:30 AM
Low oil pressure after 1.8 swap and new turbo setup JesseTheNoob DIY Turbo Discussion 15 09-30-2015 03:44 PM
why is my car running like pewp? (tune/datalog) itsMikey MSPNP 3 09-28-2015 07:40 AM
mslabs MS2 - Idle control issue ndragun MEGAsquirt 0 09-20-2015 11:28 PM


Thread Tools

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off



All times are GMT -4. The time now is 12:17 PM.