A guy I know on a differant forum said that our motors can shut down 3 cylinders to produce more heat when your motor is in cold weather. He said he belives it was somewhere in the teens. This is the first time I have ever heard this. Anyone got any feedback on this?

 

2nd gen trucks can do that. Our 3rd gen don't need it. When temp is around or below 0 ECM will change injection timing and events. Truck will idle at 1000rpm, and it will sound different than normal. As soon as you touch the brake pedal it will return to normal

 

yeah thats exactly right. my 01 used to do the 3 cyl thing when it got bitter cold. had a straight pipe and it sounded horrible, but it works. when it gets really cold, the 06 revs up right away and stays at high idle. I have the maunual high idle control set up in mine, and it works sweet. You can set the idle up so that the truck builds engine heat, keeps the truck warm, and the woman gets into a nice warm truck. (Thats good for everybody when she is happy )

 

On a 3rd gen the following is pretty close to how the ECM treats idle..

~32*F, and coolant temp is below 160*F and the brake, throttle, gears aren't touched for 2 minutes the rpms will increase to 1000 rpms, until 160*F, brake, throttle, gears, etc are touched, selected.

~15*F, and coolant temp is below 180*F the truck instantly goes to 1000 rpms up startup, and will do it again if you don't touch, gas, brake, gears, etc and are stationary for 2 minutes, and the coolant drops below 180*F.

 

Will a Smarty Jr. allow high idle on my 03 with manual trans? The dealer said the programming is not there for my model year. Has anyone used the Smarty on an 03 to do this.