Idle settings - 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 07-29-2007, 04:27 PM   #1
Elite Member
Thread Starter
iTrader: (3)
 
Mach929's Avatar
 
Join Date: Oct 2004
Location: lansdale PA
Posts: 2,500
Total Cats: 0
Default Idle settings

ok can anyone give me any tips on how to keep my idle from bouncing up and down constantly, i tried changing some stuff but nothing seems to help, also getting on the throttle i get a big dip, should i adjust the acceleration wizard, specifically what and which way?
Mach929 is offline   Reply With Quote
Old 07-29-2007, 04:48 PM   #2
Ben
Supporting Vendor
iTrader: (33)
 
Ben's Avatar
 
Join Date: Jul 2006
Location: atlanta-ish
Posts: 12,689
Total Cats: 99
Default

Ben is offline   Reply With Quote
Old 07-29-2007, 04:51 PM   #3
Elite Member
Thread Starter
iTrader: (3)
 
Mach929's Avatar
 
Join Date: Oct 2004
Location: lansdale PA
Posts: 2,500
Total Cats: 0
Default

so there's no way to get a decent idle without a variable tps?
Mach929 is offline   Reply With Quote
Old 07-29-2007, 05:24 PM   #4
Elite Member
iTrader: (5)
 
Atlanta93LE's Avatar
 
Join Date: Sep 2006
Location: Marietta, GA
Posts: 2,198
Total Cats: 1
Default

I've been struggling with the same thing. I found some guy on m.net that had success with an "85-87 735i" TPS. I found one similar on ebay (seems BMW had many similar TPS that worked on a range of cars in that era), which should arrive soon, and I'll give that a try. It would be a rather cheap solution ($13 shipped), if it works.
Atlanta93LE is offline   Reply With Quote
Old 07-29-2007, 06:35 PM   #5
Supporting Vendor
iTrader: (5)
 
Join Date: Jun 2006
Location: Duluth, GA 30097
Posts: 798
Total Cats: 0
Default

Try slowing down the 'fast recovery speed' to 10 or 15 hundredths of a second. I've updated our base settings a bit and found a combination that works a bit better and this was probably the biggest piece. The variable TPS makes a huge difference when coming off throttle coming to a stop with the AC on, but otherwise you shouldn't have oscillations like this. It's probably trying to adjust a bit too fast and getting into some oscillation.

You will need to restart the car after making the changes...
FoundSoul is offline   Reply With Quote
Old 07-29-2007, 10:08 PM   #6
Elite Member
Thread Starter
iTrader: (3)
 
Mach929's Avatar
 
Join Date: Oct 2004
Location: lansdale PA
Posts: 2,500
Total Cats: 0
Default

i'll try that, thanks
Mach929 is offline   Reply With Quote
Old 08-01-2007, 09:05 AM   #7
Elite Member
iTrader: (1)
 
Join Date: Jun 2006
Location: Warrington/Birmingham
Posts: 2,658
Total Cats: 39
Default

Quote:
Originally Posted by FoundSoul View Post
You will need to restart the car after making the changes...
Is this why whenever I tried tuning the idle I could never get it right?
richyvrlimited is offline   Reply With Quote
Old 08-01-2007, 10:50 AM   #8
Supporting Vendor
iTrader: (5)
 
Join Date: Jun 2006
Location: Duluth, GA 30097
Posts: 798
Total Cats: 0
Default

Not sure... I stated it for a pretty specific reason-- as he was having an oscillation issue, and in my experience when you're working on correcting that, once it starts oscillating, you can change the setting, but you need to restart the car to get it to settle down. Even if the new setting is right on.

That's the only idle control type situation I noticed this with however. Other settings always appear to take effect immediately and allow me to tune on the fly.

Warm-up idle tuning isn't that hard once you have the base values for your valve right.

Closed loop tuning is another story all-together, and it takes some time. It's officially 'experimental' code, and the documentation is a bit weak IMO. I had to work with it until it made sense to me, basically experimenting until I answered most of the questions I had about it. I'm fairly good at tuning it now and I've been contributing to the documentation some for MS1 Extra-- you should see some updates happening.
FoundSoul is offline   Reply With Quote
Old 08-01-2007, 12:22 PM   #9
Elite Member
iTrader: (1)
 
Join Date: Jun 2006
Location: Warrington/Birmingham
Posts: 2,658
Total Cats: 39
Default

Quote:
Originally Posted by FoundSoul View Post
Closed loop tuning is another story all-together, and it takes some time. It's officially 'experimental' code, and the documentation is a bit weak IMO. I had to work with it until it made sense to me, basically experimenting until I answered most of the questions I had about it. I'm fairly good at tuning it now and I've been contributing to the documentation some for MS1 Extra-- you should see some updates happening.
Thanks for that Jerry, I'll be honest and say I faffed around with the C/L-Idle for months. Whilst n/a I had it pretty good, but once I put the charger on it all went to pot, to the point where I've had to give up and give the stock ECU control. I just couldn't get it to stop fluctuating.

I've a feeling that some other part of my tune isn't good enough which is contributing to the problems however, as with the stock ECU controlling idle it takes a good heatsoak before the idle reaches a reasonable level, and once really heatsoaked it drops further still - setting the idle when this heatsoaked means it rev's it's **** off when cold!

Could be the coolant/IAT related air density that needs fiddling, but atm I have it set at a compromise as I've not had the time to mess with it...

I've also recently moved from Highres to standard extra code due to a missfiring issue with the high-res, and now with the loss of resolution my idle fluctuates with the stock ECU in control!
richyvrlimited is offline   Reply With Quote
Old 08-01-2007, 01:25 PM   #10
Junior Member
 
Join Date: Jun 2006
Location: LV, NV
Posts: 225
Total Cats: 0
Default

Have you tried playing with ignition timing to sort out the idle? I've found that having a few more degrees of advance at higher kpa idle speeds can help stabilize idle.

For example, my car idles with 13* at 850 rpm @ 30kpa. At 40 kpa it gets 14*, and 15* at 50 kpa. If MAP should drop at idle, the increased advance helps things stabilize. Changes in spark advance are going to affect things way before an idle valve. This is the only way I could remove my idle oscillations with the stock ecu running idle.
mschlang is offline   Reply With Quote
Old 08-01-2007, 01:41 PM   #11
Senior Member
 
Join Date: Oct 2005
Location: Knoxville
Posts: 1,168
Total Cats: 0
Default

Quote:
Originally Posted by Mach929 View Post
so there's no way to get a decent idle without a variable tps?
I don't have AC, but my car idles and comes off idle just fine without a TPS. It just needs good fuel and accel tuning.
Al Hounos is offline   Reply With Quote
Old 08-02-2007, 05:01 AM   #12
Elite Member
iTrader: (1)
 
Join Date: Jun 2006
Location: Warrington/Birmingham
Posts: 2,658
Total Cats: 39
Default

Quote:
Originally Posted by mschlang View Post
Have you tried playing with ignition timing to sort out the idle? I've found that having a few more degrees of advance at higher kpa idle speeds can help stabilize idle.

For example, my car idles with 13* at 850 rpm @ 30kpa. At 40 kpa it gets 14*, and 15* at 50 kpa. If MAP should drop at idle, the increased advance helps things stabilize. Changes in spark advance are going to affect things way before an idle valve. This is the only way I could remove my idle oscillations with the stock ecu running idle.
Not tried that no, any chance you could e-mail me your msq so I can have a look?

richard dot priest1 at googlemail dot com

Thanks!
richyvrlimited is offline   Reply With Quote
Old 08-02-2007, 02:42 PM   #13
Junior Member
 
Join Date: Jun 2006
Location: LV, NV
Posts: 225
Total Cats: 0
Default

It's on the way.
mschlang is offline   Reply With Quote
Old 08-03-2007, 05:03 AM   #14
Elite Member
iTrader: (1)
 
Join Date: Jun 2006
Location: Warrington/Birmingham
Posts: 2,658
Total Cats: 39
Default

Quote:
Originally Posted by mschlang View Post
It's on the way.
gorrit! thanks
richyvrlimited is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
OTS Bilstein to motorsports ASN conversion stoves Suspension, Brakes, Drivetrain 5 04-21-2016 04:00 PM
Changing from 460cc to flow force 610cc in diypnp 90 Turbo MEGAsquirt 19 10-19-2015 04:23 PM
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
Leaky Wilwoods mx592 Suspension, Brakes, Drivetrain 1 10-01-2015 01:45 AM


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 12:31 AM.