EvoScan Actuator SAS Mode
Aug 3, 2008, 08:00 AM
#16
Account Disabled
iTrader: (3)
Join Date: Apr 2006
Location: USA
Posts: 1,029
Likes: 0
Received 0 Likes
on
0 Posts
Base Idle Set Screw
In the DSM's we used to have to jumper a diagnostic connector in the engine bay to set the BISS. It would basically zero out the IAC so that you could set the idle speed to spec. A more intuitive name would be "BISS setting" or "BISS adjustment".
Their was also another connector in the engine bay that you would jumper to ground as well to fix the ignition timing to 5 degrees ATDC so that you could set your timing to spec as well with a timing light. You might run into that in the future even though the evo has a mostly fixed timing adjustment range.
In the DSM's we used to have to jumper a diagnostic connector in the engine bay to set the BISS. It would basically zero out the IAC so that you could set the idle speed to spec. A more intuitive name would be "BISS setting" or "BISS adjustment".
Their was also another connector in the engine bay that you would jumper to ground as well to fix the ignition timing to 5 degrees ATDC so that you could set your timing to spec as well with a timing light. You might run into that in the future even though the evo has a mostly fixed timing adjustment range.
Last edited by dan l; Aug 3, 2008 at 08:05 AM.
Aug 3, 2008, 09:43 AM
#18
clipped out of the manual SAS =speed adjusting screw, Not secondary air system
NOTE: The standard idle speed has been adjusted with the
speed adjusting screw (SAS), by the manufacturer, and there
should be no need for readjustment.
NOTE: If the adjustment has been changed by mistake, the idle
speed may become too high or the idle speed may drop too low
when loads A/C, defogger, etc. are placed on the engine. If this
occurs, adjust by the following procedure.
NOTE: The adjustment, if made, should be made after first confirming
that the spark plugs, the injectors, the idle air control
motor, compression, etc., are all normal.
1. The vehicle should be prepared as follows before the
inspection and adjustment.
• Engine coolant temperature: 80 − 95°C (176 − 203°F)
• Lights, electric cooling fan and accessories: OFF
• Transaxle: Neutral
CAUTION
To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before connecting
or disconnecting scan tool MB991958.
2. Connect scan tool MB991958 to the data link connector
(16-pin).
3. Start the engine and run at idle.
4. Select the item number 30 of the scan tool Actuator test.
NOTE: Use the scan tool to hold the IAC motor at the basic
step to adjust the basic idle speed.
5. Check the idle speed.
Standard value: 850 ± 50 r/min
NOTE: The engine speed may be 20 to 100 r/min lower than
indicated above for a new vehicle [driven approximately 500
km (300 mile) or less], but no adjustment is necessary.
NOTE: If the engine stalls or the engine speed is low even
though the vehicle has been driven approximately 500 km
(300 mile) or more, it is probable that deposits are adhered
to the throttle valve, so clean it. (Refer to P.13A-813.)
NOTE: The standard idle speed has been adjusted with the
speed adjusting screw (SAS), by the manufacturer, and there
should be no need for readjustment.
NOTE: If the adjustment has been changed by mistake, the idle
speed may become too high or the idle speed may drop too low
when loads A/C, defogger, etc. are placed on the engine. If this
occurs, adjust by the following procedure.
NOTE: The adjustment, if made, should be made after first confirming
that the spark plugs, the injectors, the idle air control
motor, compression, etc., are all normal.
1. The vehicle should be prepared as follows before the
inspection and adjustment.
• Engine coolant temperature: 80 − 95°C (176 − 203°F)
• Lights, electric cooling fan and accessories: OFF
• Transaxle: Neutral
CAUTION
To prevent damage to scan tool MB991958, always turn the
ignition switch to the "LOCK" (OFF) position before connecting
or disconnecting scan tool MB991958.
2. Connect scan tool MB991958 to the data link connector
(16-pin).
3. Start the engine and run at idle.
4. Select the item number 30 of the scan tool Actuator test.
NOTE: Use the scan tool to hold the IAC motor at the basic
step to adjust the basic idle speed.
5. Check the idle speed.
Standard value: 850 ± 50 r/min
NOTE: The engine speed may be 20 to 100 r/min lower than
indicated above for a new vehicle [driven approximately 500
km (300 mile) or less], but no adjustment is necessary.
NOTE: If the engine stalls or the engine speed is low even
though the vehicle has been driven approximately 500 km
(300 mile) or more, it is probable that deposits are adhered
to the throttle valve, so clean it. (Refer to P.13A-813.)
The following users liked this post:
phantastic (Feb 17, 2023)
Aug 4, 2008, 03:34 PM
#19
This works awesome!
I did the SAS actuator test, and the IAC stopped and idle went to down 700 rpm and hunting. I adjusted the idle screw to bring idle to 900 rpm, turned off the test and after a while idle stabilized to 900-950rpm. Engine idles strong and feels smoother transitioning from cruise to idle at a stop.
I did the SAS actuator test, and the IAC stopped and idle went to down 700 rpm and hunting. I adjusted the idle screw to bring idle to 900 rpm, turned off the test and after a while idle stabilized to 900-950rpm. Engine idles strong and feels smoother transitioning from cruise to idle at a stop.
Aug 6, 2008, 10:12 PM
#25
I upped the idle to around 925rpm. My cams dont like to idle smoothly. The car idles pretty smooth and even runs with the A/C on. Will test drive tommorrow, Initiallt it was idling at about 450-500 when I activated the SAS and died twice before I could get it adjusted.
Aug 7, 2008, 12:18 AM
#27
Evolving Member
If you bump up too much - the ecu will not be able to get down to the pre-programmed rpm (in one of the tables 
- and then it throws an "idle control malfunction" code.
- and then it throws an "idle control malfunction" code.
Aug 7, 2008, 05:37 PM
#28
Base setting is used to match the set ECU value with sas +/-50rpm.
IF you change the rpm idle value(ECU) to 900rpm use SAS test to set rpm to 900. Opposed to just attempting to raise rpm with SAS without changing ecu value, IAC would bring back to 850 rpm.
This will allow the ECU to control the IAC and match that value with out having to open too much.
IF you change the rpm idle value(ECU) to 900rpm use SAS test to set rpm to 900. Opposed to just attempting to raise rpm with SAS without changing ecu value, IAC would bring back to 850 rpm.
This will allow the ECU to control the IAC and match that value with out having to open too much.