Strange start-up on 6.0

Scott B · October 16, 2006

This is my own Tk it is a 4-04 build SD. and It has only had one reflash and a EGR valve so far.The temps are getting colder in my neck of the woods now, freezing is about the coldest its gotten yet.The tk is displaying some weird behavior on cold starts in the morning.It fires right up but it now has the real Loud brapp sound like the original 03's used to have when firing off.Also you would swear it had pilot Injection after starting.It is unbelieveably quiet for about 10 minutes of Idling.Then it gets considerably louder (Normal)sounding.Another thing is when it is idling quietly like this you can rap the pedal and it will act just like a engine with pilot injection it will bark and go back super quiet again.It has never done this before in cold temps or any other time for that matter.It is not causing any problems and the tk runs strong.It is just strange how now its doing this.Its never had any tuners or boxes on it.Hopefully I am not heading for a ECM failure

Keith Browning · October 17, 2006

When was the last PCM reflash done and just how cold are we talkin about in Pennsylvania? The really quiet idle is what has my attention. Unfortunately I don't own one of these trucks so I don't get to see the seasonal effects like the owners do.

Cetane · October 17, 2006

While I am certainly no 6.0L expert I will give this my two cents. If the engine is running audibly quieter is is normally only four things: too much EGR(i.e. stuck valve), retarded timing, an additional injection or lack of main injection. An additional injection, all of the sudden popping up, seems pretty unlikely. Retarded timing also seems unlikely although could happen if the CKP/CMP is reading incorrectly. Lack of fuel mass injected could certainly be the cause but you would likely feel that in all rpm ranges and the idle should be some what unstable, since you didnt say it was...that leaves the EGR valve which given the 6.0's history seems the most likely suspect. I would say you cheapest/easiest course of action would be to pull it out and clean it. If that doesnt fix it then look at the other areas. Again I am not a 6.0 expert but hopefully this gives you something to look into.

Jim Warman · October 17, 2006

I kinda like Cetanes thought track.... The quiet idle would have me pulling the EGR and looking for signs of wet stacking... Soot is going to be normal.... gooey sh*t is "normal" but not right.

You could look at MF_DES and LOAD.... I still haven't correlated much more than high MF_DES plus high LOAD = bad injector(s) but these PIDs might be useful for other concerns I have yet to see.

Failing that, we haven't discussed engine oil.... Maybe a buzz test while listening closely to what is heard and forgetting about the electrical portion of the test???? I am still sure that "stiction" isn't a real word, but it is a real condition.

FWIW, we run 10W30 in the summer, 0W30 in the winter and spec our oil changes as "severe duty".

Scott B · October 17, 2006

As far as Temps go we are only talking freezing 32 degree's.So really not that cold.It has started up at near 0 outside without the block heater with just a little normal smoke normal souding combustion.It is the sound of it now that is wierding me out and how it acts in this short time,I gaurantee you would absolutely think it has Pilot Inj.The EGR was just replaced this summer Its only flash was done in 0ct 05 # 4U7A-124650 BFG on the Re-cal Tag.I have always run the rotella 5-40 syn with NO issues.I am almost thinking it could be a ICP issue with the way the tone changes.I know timing would also make it do that.I cannot use The International software on it at work so I may take it to Ford.The thing is it isnt a actual problem and I dont want to crack open a Hornets nest over it,Or waste another Techs time.Maybe its this winter Fuel, I believe it is out around here Now.Also I think that the ULSD is at the pumps Nationwide now, or the Deadline is sometime this month that every refinery must be in complience.