High Idle

[dieseldork]

Its been a while since I have been on the sight, But I have a question for the GURUS..... When its cold out and the truck idles for a while, the idle kicksup on the truck?........ when I jump back in and tap the brakes it will return to a normal idle ..... What gives?... Is this normal and what is the reason?
It will also kick back on if I continue to let her idle. It only does it when its in the 30s, or lower.

 

[fgtex]

It is normal for these trucks to do. It is a built in high idle to help the engine warm up when it air temp is cold.

 

[dieseldork]

Thanks FGTEX, I havent had the truck through a winter yet so This was a new one for me....

 

[fgtex]

The EBPV closes to help the vehicle warm up also. Go stand by the exhaust while it is on high idle and the EBPV closed...it sounds pretty cool.

 

[melmount]

whats the ebpv valve?

 

[00F250]

EBPV - Exhaust Back-Pressure Valve

 

[Yellowsub1962]

I've also read lots of places that the high idle keeps the cylenders frow washing out as well?

 

[DaveBen]

I think you mean "cylinders".

Dave

 

[powerstrokeguy]

yep i heard that too. yeh its just a warming device. they all do it in cold temps.

 

[bushpilot]

Im not sure i agree w/ the "warming" device...its more of a wet stacking
issue i think.

My experiance is that no matter HOW warm the truck, if the out side
air is below some temp. (40* or so...) the idle will kick up automatically...
and it doesnt matter if you just started the truck or youve stopped
and are "idling" (having just run the truck).

so i tont thing kits a "warmth" (of the engine) issue...its more of
an outside air temp issue