How to change idle speed with Tech II scan tool
Confirmed! Tech II scanner is able to raise and lower the idle!
It’s possible for GM vehicles to get the ecm reprogrammed for the fast idle increase. your local dealer should be able to help you out. here is how it works.
Programming ECM For PTO Idle Up Operation
Tech II scanner
2001-2007 Chevrolet Silverado Classic
2003-2009 Chevrolet Kodiak
2001-2007 GMC Sierra Classic
2003-2009 GMC TopKick
with 6.6L or 8.1L Engine
Connect the Tech 2 and follow the steps below to program the ECM for idle up feature with PTO operation:
Turn on tech 2 and build the vehicle
select "Powertrain" (Or "Vehicle Control Systems" on later models)
select "Special Functions" (or "Module Setup" on later models)
select "PTO Options"
select "Change Options" (soft key at bottom of the screen)
select F1 "PTO Preset Speed Control"
select pto max engine speed set to 2200 - 4400 rpm (not below 2200)
These steps will not allow the engine rpm to exceed the rpm setting, even during normal driving if the PTO switch is on
select stand by speed (base fast idle ) set to 1200 (this setting is initial fast idle)
select PTO set speed - set to 1400 rpm
select PTO resume speed - set 1700 rpm
select PTO max engage speed - set to 1800 rpm (PTO engagement inhibit speed)
select PTO engine shutdown - no
select PTO engage relay - no
select PTO feed back -no
select "Reprogram" (soft key at bottom of screen) "Waiting For Data" displays on screen-once data comes back verify settings remain
key off- until tech 2 "beeps" and screen shows "no communication" (Very important step if missed setting will not store)
key on - verify settings remain on list