Engine/Transmission (1998.5 - 2002) Factory High idle/ 3 Cylinder and EBrake

[JJW_ND]

Just an observation I had this morning that I thought might be useful to some of you.



My 2001 6sp work truck got real cold last night (-21). Truck has an Ebrake and was flashed a year ago for high idle and 3 cylinder. We use the Ebrake all the time to help warm things up. I also notice the high idle would still work with the Ebrake on and this seem to really make for quick heat. I had experience the 3 cylinder idle nor the relation to the Ebrake.



It was not going to be used in the AM so it was not plugged in. Well someone decided they needed to go somewhere at first light. It did not start (no surprise there).



Added battery charger and go it going. I quickly turned on the EBrake to help generate some heat (really helps). Very shortly the idle begin to ramp up to 1200 (this I expected... . really making heat now). I wonder if the 3 cylinder idle would kick in, never heard it before as I NEVER would tried starting this without plugging in. Sure enough, the 3 cylinder kicked in, engine almost died (EBrake still on) and the computer quickly turned off 3 cylinder and high idle. I then turn off the Ebrake. I idle ramped up, and in minute or so 3 cylinder kicked. Boy did if sound like *****. I left the Ebrake off as I would think it would again kill the motor turn off the high idle etc.



I would think High Idle and Ebrake would help the engine more then High idle and 3 cylinders. Might have to look into turning off just he three cylinder option if that is an option.



FYI!



jjw

ND

 

[jtisdale]

I have wondered this also...

Its no surprise that the high idle worked with the brake on. I notice 400-500 egt's with the 3 cylinder engaged, but I dont have my PAC on yet, so I dont know what a Brake and/or a high idle condition would show for egt's. It is intresting to note the 03's also have the high idle (I assume from factory no flash required) enabled, but they also have a feature that if you have an exhaust brake, it will automatically turn it on. This makes me wonder if they have given up on the 3 cylinder shutdown feature, as I havent heard of an 03's coming from the factory with the 3 cylinder shutdown feature?? Maybe DC had problems with the 3 cylinder shutdown feature. Also, It will be intresting to see if they retro fit a program so our trucks (with brakes) will behave like they 03's.

Any thoughts??

 

[Michael Hughes]

I also had my eBrake on when the engine went into 3 cylinder mode. It was close to killing it. I switched the eBrake off and let the engine warm up a little. I turned it back on, I was seeing close to 1,000F EGT. I turned the eBrake back off. Man does it make some noise at 1,200 RPM in 3 cylinder mode with eBrake on!!