I recently had the high idle enabled on my truck, as a matter of fact, I haven't driven the truck since I did that.  I went out this morning to start it and it had a heck of a time firing.  It would try to start, catch for just a second and then die.  I cycled the grid heaters a couple of times, not sure if that helped.  It finally did start and it ran like a pig. I've never seen, first hand, a truck run on 3 cyl, but I imagine this was it.  It seemed like there was a miss, sounded awful.  You should have seen my wife's face when I went back in the house.  After about 10 seconds the idle changed in an instant and ran smooth; the RPMs ran up to around 1200ish (High idle?) 

Before flashing the ECM, I have never had any rough starts like this in the cold, the temp this morning was only about 25*, never any issues starting in colder temps.  Maybe cold fuel??

I am questioning why it was such a tough start.  It shouldn't have started in 3 cyl because it was cold enough, right?  It wasn't plugged in, I'm sure that would have helped.  Any thoughts, or is this normal High Idle software activity?

2 hours ago, Buzzinhalfdozen said:

Your neighbors must love you

I agree, they must be on a first name basis.

I checked the voltage this morning.  The first cycle, at both posts on the grid there was just over 9 VDC.  The FSM said there should be 12....hmmm.  With each post, as I held it there,. the voltage quickly dropped until the relay swapped.  The second cycle, the voltage started closer to 7 vdc.  Something isn't right.  I checked the batteries each time, and when the grids were cycling they were showing 11.55 VDC.  And just over 12 when the grids weren't on.  It is a little warmer today and it started up just fine.

Those voltages sound about normal for engine off and decent batteries. The grids have a huge amp draw which drops the voltage accordingly. You will never see 12V at the grids with the OEM batteries/alternator and the grids on. 

On ‎11‎/‎24‎/‎2015‎ ‎2‎:‎22‎:‎04‎, Buzzinhalfdozen said:

Your neighbors must love you

 

On ‎11‎/‎24‎/‎2015‎ ‎5‎:‎05‎:‎45‎, gh0stman said:

I agree, they must be on a first name basis.

I normally park in BFE, but I knew I wouldn't be leaving early so I parked close. I think they would hate the 3cyl idle every morning more than a little smoke.

1 hour ago, TFaoro said:

I normally park in BFE, but I knew I wouldn't be leaving early so I parked close. I think they would hate the 3cyl idle every morning more than a little smoke.

Very considerate. I am sure there are a few of my neighbors that dislike my truck in the early 4am departures... but I outrank all of them.   

I try to be nice though and not idle around at the house.