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Idle Issue, Please Help

KiNgMaRtY

Well-known member
Joined
Apr 8, 2008
Messages
855
Location
Corona, CA
So before MOD, I decided to finally relocate my battery to where the OEM intake box would be and install a 2g Intake. I sourced out a rare Greddy 3" 2g Intake and installed it along with a 2g MAS. I put on a reducer coupler going in to the E316g. I installed ECMlink V3 and pulled out the Keydiver chip it had in there. I disconnected the SAFC2 it had on there and just rewired the MAS wire back to the ECU. I left the other wires tapped into the ECU from the SAFC2 and disconnected harness.

I start the car and the idle is fine. Car warms up and I rev it and I get idle surge. It then sits at like 1800-2000 rpm. I made sure I chose 2g MAS on link as when I ordered it they sent it to be using a 3g mas. I have to use a 2g Mas to match up the intake pipe. It drives great, but it just won't idle right.

Next day I start the car and just let it sit for like 10min and the idle is fine till I rev it a little and then the surge and high idle begins.

Car was working with no idle issues before I installed link and the 2g Intake setup so I am kind of in doubt it can be the ISC.

Any suggestions would be greatly appreciated.
 
Last edited:

KiNgMaRtY

Well-known member
Joined
Apr 8, 2008
Messages
855
Location
Corona, CA
I started the car and did not hit the throttle. Let the car warm up and it idles fine. I adjusted ISCPosition to 30

I then gave it a little throttle and let the surging begin.
I did the simulate and it got my idle at a steady 1800 RPM. Clicked it back off to have the switch back on and my idle dropped back to 1300 but recommenced surging.

I took some logs

This is when I hit simulate
TPS Simulate.elg

Idle Surge:
Idle Surge Log.elg
TPS Simulate.elg
 
Last edited:

nandovr4

Member
Joined
May 11, 2010
Messages
23
Location
Placerville, CA
I believe this is a vacuum issue. I'm dealing with the same thing right now. It is my guess that there is too much air getting passed the butterfly on the throttle body. On mine I can close the butterfly all the way and it still idles, but it should die. I would check the throttle body for leaks. I will be testing the theory on my own car.

Here are a couple of links to help:
click
click
click
click
click


Fernando
 

KiNgMaRtY

Well-known member
Joined
Apr 8, 2008
Messages
855
Location
Corona, CA
Thank you, I will look through the links. I don't think I have a TB issue as all I did was put in the 2g intake, 2 MAS, ECMlink and relocate the battery and then as soon as I start it, I have this problem
 

Overkill

Well-known member
Joined
Dec 10, 2006
Messages
48
Location
Berthoud, CO
Are all the coils in your ISC good because if a few are bad your ISC will not control the idle properly. A DSM member of codsm.org rebuilds them if you find yours to be bad and want it rebuilt. He has done a few for me and also does ECU repairs.
 

KiNgMaRtY

Well-known member
Joined
Apr 8, 2008
Messages
855
Location
Corona, CA
I will have to check it but I don't think it may be the issue because before I give it that rev, it idles fine and I was able to adjust the position via the BISS screw correctly. It literally happened from before to after the install of the new items
 
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