Riddle me this - Miata Turbo Forum - Boost cars, acquire cats.

Welcome to Miataturbo.net   Members
 


General Miata Chat A place to talk about anything Miata

Reply
 
 
 
LinkBack Thread Tools
Old 11-09-2009, 03:09 AM   #1
Elite Member
Thread Starter
iTrader: (1)
 
NA6C-Guy's Avatar
 
Join Date: Feb 2008
Location: Birmingham Alabama
Posts: 8,038
Total Cats: 43
Default Riddle me this

What the **** is a SGT and SGC signal? I'm throwing a 3 or 4 code forget which one it was. Any idea.

While I am at it, what is an ISC valve? That little bastard on the right fender with hoses going to it and a single multi pin connector. Mine has been capped off and unplugged since the rebuild, what is that possibly causing?

Sorry, this is a drunk request post.
NA6C-Guy is offline   Reply With Quote
Old 11-09-2009, 03:26 AM   #2
Elite Member
iTrader: (24)
 
Join Date: Jun 2007
Location: Sherman Oaks, CA
Posts: 4,481
Total Cats: 3
Default

isc valve opens on idle to allow in for air to keep idle. i think that it only adds additional air to compensate for rich conditions or something and actual air to keep idle comes from throttle body. i had extremely rough idle when i accidentally disconnected mine back with oem ecu on my red '96.

sorry if parts of my post dont make sense. took me good 20 minutes to type it up... stoned out of my mind
UrbanSoot is offline   Reply With Quote
Old 11-09-2009, 03:32 AM   #3
DXO
Junior Member
iTrader: (2)
 
Join Date: Jul 2008
Location: Kannapolis, NC
Posts: 229
Total Cats: 1
Default

SGT and SGC signal comes from the CAS. Codes 3 and 4 mean the ECU isn't getting one of those signals. Take that as you may, it may be failing or maybe just a loose connection.

ISC(Idle Speed Control) = Idle air control

No more drunken posting.... unless you are flat out wasted so we can all laugh.
DXO is offline   Reply With Quote
Old 11-09-2009, 03:48 AM   #4
Junior Member
 
Join Date: Nov 2009
Location: Jax Fl
Posts: 469
Total Cats: 30
Default

Quote:
Originally Posted by DXO View Post
SGT and SGC signal comes from the CAS. Codes 3 and 4 mean the ECU isn't getting one of those signals. Take that as you may, it may be failing or maybe just a loose connection.

ISC(Idle Speed Control) = Idle air control

No more drunken posting.... unless you are flat out wasted so we can all laugh.
Thx for the info
Tw34k is offline   Reply With Quote
Old 11-09-2009, 04:33 AM   #5
Elite Member
Thread Starter
iTrader: (1)
 
NA6C-Guy's Avatar
 
Join Date: Feb 2008
Location: Birmingham Alabama
Posts: 8,038
Total Cats: 43
Default

The ISC makes sense. My idle has been a bit low and rough since the rebuild. I broke a nipple off the valve and just said **** it and capped off the nipples on the plenum and left the valve unplugged. Not sure about the CAS issue. Would it run correctly without on of those signals? Wouldn't throwing those codes mean you should have a car that either won't run or runs very badly? I do have a bad case of detonation lately, but I was just thinking thats my higher compression ratio and too much advance on the timing. Maybe its not CAS related. I can't afford a new CAS right now, since they are like $500.
NA6C-Guy is offline   Reply With Quote
Old 11-09-2009, 04:34 AM   #6
Elite Member
Thread Starter
iTrader: (1)
 
NA6C-Guy's Avatar
 
Join Date: Feb 2008
Location: Birmingham Alabama
Posts: 8,038
Total Cats: 43
Default

Quote:
Originally Posted by UrbanSoot View Post
isc valve opens on idle to allow in for air to keep idle. i think that it only adds additional air to compensate for rich conditions or something and actual air to keep idle comes from throttle body. i had extremely rough idle when i accidentally disconnected mine back with oem ecu on my red '96.

sorry if parts of my post dont make sense. took me good 20 minutes to type it up... stoned out of my mind
Aww man, stoned post. Maybe I won't die from taking Ambien sleeping pills and some Jager shots. I do feel a bit... funny...
NA6C-Guy is offline   Reply With Quote
Old 11-09-2009, 04:52 AM   #7
Junior Member
 
Join Date: Nov 2009
Location: Jax Fl
Posts: 469
Total Cats: 30
Default

Yeah if you capped off the isc valve id imagine thats going to be the source of the idle issue and most likely it also causes the car to "buck" under most low throttle areas when trying to cruise.

From what i understand the CAS is pretty important when it comes to the stock ecu for proper operation.

Last edited by Tw34k; 11-10-2009 at 12:24 AM.
Tw34k is offline   Reply With Quote
 
 
Reply

Related Topics
Thread Thread Starter Forum Replies Last Post
Lets argue about VGT/VNT Diesel Turbos on a gas motor. Pinky DIY Turbo Discussion 61 03-26-2016 04:24 PM
Pride In Your Ride JakeAlex302 General Miata Chat 64 04-18-2014 08:14 PM
'04 ABS Can't Use Prop Valve mr_hyde Suspension, Brakes, Drivetrain 31 12-19-2013 12:39 AM
What is big government? mgeoffriau Current Events, News, Politics 0 08-09-2012 12:50 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 10:15 AM.