Someone please school me on this. What is the actual purpose of the high idle option?

 

Several useful purposes. First is to control the engine RPM when driving a PTO device. This one uses the SEIC, Stationay Engine Idle Control. It gradually ramps up the RPM's to whatever setpoint you select via a pot. Or it can just be a fixed RPM. This version locks your torque converter so it will drive the PTO.

Second is just a BCP, or Battery Charge Protect. This one is intended for vehicles that may use a lot of electrical current, and could discharge the batteries while at idle. It basically locks at a minimum of 1,200 RPMs, and most of us never see more than that, but it has the capability of increasing the RPM's up to 2,400 if necessary to handle the current load. This version does not lock the TC.

It is also used to keep the idle high to prevent wet stacking, and in the case of the 6.0, EGR carbon buildup. This is because a diesel will lose operating temp at an idle, and it can drop to an inefficient temp to burn cleanly. The owners manual alludes to that just briefly. Wet stacking on the other hand is well known.

I also use it when I park briefly and want my AC to keep the cab cool. I also use it after a fuel filter change, when I want to be sure all the bubbles are purged out of the fuel system.

It is most useful with the diesels, but it is available on the gassers too, although the RPM's are a little different.

 

up here in Canada when it's cold out (winter), the idle goes to 1000 RPM on my 2006 untill the engine warms up & I have no control over it,Gigger

 

As I understand it, the wet stacking problem happens during cold ambient temps when normal operating temp is harder to maintain as mentioned above. I thought it would be nice to have as far as being able to let the engine warm up a bit in the winter. Paired up with a block heater, the high idle mod should get the engine, and consequently the heater core, up to temp a bit quicker which greatly decreasing the complaining from the family. I also winch logs onto a trailer on occasion and the extra revs can't hurt as far as electrical load. I believe Ford's mantra is "just turn it off" rather than idle, but for my money, I would have to think the engine would like it better to stay at a stable temp than cycle on and off every time I had to wait on the wife when "I'll just be a minute" comes into play.
In reading the manual, the 6.0 is supposed to idle up without this mod during certain cold temp conditions but it apparently doesn't take care of the problem of wet stacking completely.
Eric

 

Gigger, the truck has a built in high-idle kick that comes on when the engine temp is below a threshold, it's the built-in version of the high idle mod to prevent things like wet stacking when it's cold and the user doesn't take any action.

I use my mod mainly when I'm pulling people out of ditches, or idling waiting to pull a stock trailer when it's cold, figure every bit helps when I'm gonna load the engine down when it's really cold outside.

 

I let my engine warm up even in the summer at normal idle,is that ok? I'm not sure what the term "wet staking" refer's to ,can anybody tell me? thx Gigger

 

Extensive idling is bad for a 6.0, with or without high idle. The high idle makes it less of a problem, but doesn't make it a good thing.

Wiki says this about wet stacking:
Wet stacking - Wikipedia, the free encyclopedia

It's basically unburned fuel in the cylinders due to low combustion chamber temperature. That creates a lot of oily soot, which is where the EGR in our 6.0 becomes an issue. It can also wash the oil off of the cylinder walls, and in non-vertical cylinders like our V-8, it can lead to cylinder wall scuffing. For us 6.0 owners, it's the EGR system that worries us the most IMO.

 

thanks BPOUNDS for bringing that to my attention,I will keep an eye on it,Happy New Year to everybody, thx Gigger