High idle??

[beerhunter]

99' 7.3l

On chilly mornings (20's-low 30's) I will start the pickup about 10-20 minutes before I leave home. The truck always starts fine. On occasion when I come out of the house to leave, I notice the truck idling a little high. When I jump in and give her a little right foot then the rpms will return to the normal idle around 1,500 or so.

Almost forgot to mention that the high idling is slightly under 2,000 or just enough that I can hear that it is idling higher than normal.

Is this abnormal?, any thoughts are appreciated.

thanks,

[djsdiesel]

The pcm is programmed if the parmeters are met(engine oil temp, intake air temp. and long enough idle time) the engine idle will raise.

[beerhunter]

I do not understand that. Can anyone explain further in more detail.

[stump0331]

let me bump this up for ya, somebody ought to be able to explain further

[MR.BIGHILLBILLY74]

Yes this is normal for those of us who live in the colder areas! I have the 6.0 and when I start it on cold mornings it will kick up the idle to heat the motor up faster. There is nothing wrong with your truck. Even if you plug it in overnight and then start it, it will do the same thing!

[Marty]

Originally Posted by beerhunter

99' 7.3l

On chilly mornings (20's-low 30's) I will start the pickup about 10-20 minutes before I leave home. The truck always starts fine. On occasion when I come out of the house to leave, I notice the truck idling a little high. When I jump in and give her a little right foot then the rpms will return to the normal idle around 1,500 or so.

Almost forgot to mention that the high idling is slightly under 2,000 or just enough that I can hear that it is idling higher than normal.

Is this abnormal?, any thoughts are appreciated.

thanks,

Your #'s sound high, but yes the 7.3 will increase its idle slightly depending upon a few variables mentioned in the first response.

[djsdiesel]

basically if it's cold the computer will tell it to high idle, to aid in warming, and to try to prevent wet stacking.

[beerhunter]

Thanks for the info.
If I were to let it idle will it eventually return to normal when it reaches certain parameters.

Also, can you define wet stacking?

[stump0331]

I DIDNT KNOW EITHER so i looked it up for up

Wet stacking occurs in a diesel engine when the engine is run at too light of a load during the run-in (also known as load banking). This causes unburnt fuel and oil to collect in the exhaust stack. The exhaust stack will be coated with a black, sticky, tar-like substance. If you run a new unit at light loads and/or idle for too long, the rings will not seat properly. If it is a diesel, wet stacking may occur. Both of these conditions will cause poor engine life and performance.

[djsdiesel]

I don't know if it will return to idle afer a long period. If you press the brake pedal, or throttle it will return to normal idle. but if you touch the break and then let it idle again it will raise the idle again.