High Idle, possibly IAC releated? - 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 02-14-2008, 12:25 AM   #1
Junior Member
Thread Starter
 
Join Date: Apr 2006
Location: santabarbara,ca
Posts: 97
Total Cats: 1
Lightbulb High Idle, possibly IAC releated?

Just put the original throttle body from the 1.8 engine that i have in my car back on. In addition I loaded the firmware from the 9697 mspnp (HR10e) so i could get the hi res. The car starts up and seems to run and drive fine, however the idle is around 2000rpm. I have the idle adjustment screw all the way in, seems to be where it idles lowest. The timing is a-ok, and I haven't found any vac leaks. I believe the IAC may have something to do with it. I'm not really sure if i have these wires hooked up correctly or even if the IAC on this TB works right (how do I test?)
Name:  iac.jpg
Views: 8
Size:  35.5 KB
Also what is this sensor for the one circled in red?
Name:  sensor.jpg
Views: 6
Size:  67.8 KB
One last thing do i have to have these nozzles plumbed into the cooling system, or can i just bypass, and if so which is in and which is out?
Name:  nozzles.jpg
Views: 7
Size:  31.8 KB
thanks!!
cheesecow1 is offline   Reply With Quote
Old 02-14-2008, 12:40 AM   #2
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,915
Default

Testing the IAC solenoid pretty much has to be done by removing it from the TB and visually observing it operate. For the moment, you could check the resistance between the two terminals to at least verify that the winding is good- if you have access to an ammeter that would be better as it would verify the drive circuit as well. For the time being, change one of the gauges on your megatune dashboard to idleDCGauge to verify that MS is at least attempting to control it.

The device circled in red isn't a sensor, it's a solenoid. Specifically, it's the charcoal canister purge valve. An emissions control device. Since you've removed the hose that goes to the charcoal canister, I suppose a leak is possible.

The two nipples on the bottom of the IAC assembly should be plumbed in, that's why they are there. There is no in and out- they'll flow either way. The coolant just passes through and warms the IAC assembly a bit.
Joe Perez is online now   Reply With Quote
Old 02-14-2008, 12:44 AM   #3
Junior Member
Thread Starter
 
Join Date: Apr 2006
Location: santabarbara,ca
Posts: 97
Total Cats: 1
Default

gratze goin to the garage to play around right now, will report back in a bit
cheesecow1 is offline   Reply With Quote
Old 02-14-2008, 01:05 AM   #4
Junior Member
Thread Starter
 
Join Date: Apr 2006
Location: santabarbara,ca
Posts: 97
Total Cats: 1
Default

okay fired up megatune and checked the value in that gauge and it does indeed try to change from 12% without car on to 9% while car is running however no change is observed when this happens (are the wires hooked up to it properly?) I am using the 9697 .msq on the car right now which is probably causing some trouble what should i change to lower the idle in megatune ve table? spark advance?
cheesecow1 is offline   Reply With Quote
Old 02-14-2008, 01:10 AM   #5
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,915
Default

Can we see an MSQ or at least screenshots of your two idle setup pages? Those values seem abnormally low for the stock IAC valve.

edit: also, verify for me that the gauge you were looking at was scaled from 0-100%, not 0-255 absolute.
Joe Perez is online now   Reply With Quote
Old 02-14-2008, 01:14 AM   #6
Junior Member
Thread Starter
 
Join Date: Apr 2006
Location: santabarbara,ca
Posts: 97
Total Cats: 1
Default

theres the msq im using
yea its scaled properly
Attached Files
File Type: zip blah.zip (5.5 KB, 47 views)
cheesecow1 is offline   Reply With Quote
Old 02-14-2008, 11:03 AM   #7
Boost Pope
iTrader: (8)
 
Joe Perez's Avatar
 
Join Date: Sep 2005
Location: Chicago (Over two miles from Wrigley Field. Fuck the Cubs. Fuck them in their smarmy goat-hole.)
Posts: 26,317
Total Cats: 1,915
Default

Interesting...

I just noticed that DIY's settings for IAC duty cycle are quite different between 90-93 and 94+. In my Idle Control screen I have minimum (dc) at 17, Closed (dc) at 16. But then the values you have match DIY's values for a 94-95...

Any 1.8 owners care to chime in here?
Joe Perez is online now   Reply With Quote
Old 02-14-2008, 11:47 AM   #8
Boost Czar
iTrader: (61)
 
Braineack's Avatar
 
Join Date: May 2005
Location: Chantilly, VA
Posts: 72,860
Total Cats: 1,788
Default

Name:  sensor.jpg
Views: 8
Size:  67.8 KB

this is for your charcoal canister...you probably don't have....unplug the solenoid and remove the vacuum line from the IM.
Braineack is online now   Reply With Quote
Old 02-15-2008, 03:05 PM   #9
Junior Member
Thread Starter
 
Join Date: Apr 2006
Location: santabarbara,ca
Posts: 97
Total Cats: 1
Default

yea i figured that is what it was for, just didn't know if it had any mission critical functions, i removed the charcoal canister cause it was unneeded weight
cheesecow1 is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Project Gemini - Turbo Civic on the Cheap Full_Tilt_Boogie Build Threads 58 Yesterday 10:04 PM
OTS Bilstein to motorsports ASN conversion stoves Suspension, Brakes, Drivetrain 5 04-21-2016 04:00 PM
My solution for Oiltemp and Oilpressure input into Megasuirt (MS3) Zaphod MEGAsquirt 41 01-24-2016 01:25 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


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 09:23 AM.