Lets play a game of what caused it....

[rockola1971]

The subject: 2005 Yukon Denali...for those that dont know....that means factory 6.0 and AWD.
Short background: Yukon has been sitting in drive for an extended period of time.
Symptoms: Hard to start, Blowing major white smoke, Reduced Engine Power on the DIC, wont get to normal idle speed, idles erratically.

I suspected bad gas so I threw in some octane booster, 4 gals of new 87 octane and some HEET. Didnt fix anything.

Ill take all guesses as to the cause of this mess until 10/26/23 1700 EST before I post pic of the cause.

Ill give you 3 clues. (1) Its not a bad battery (2) There are no fuel leaks (3) I dont live in the City.

 

[swathdiver]

Coolant into the combustion chamber(s).

 

[Doubeleive]

VARMIT IN THE INTAKE, NEST ETC,doesn't really explain the white smoke but that's my guess

 

[OR VietVet]

Lean condition caused by a rodent. Haven't figured how yet. I suspect something to do with harnesses effecting fuel delivery or.......

The part about major white smoke can be a lot to one person and not so much to another. The consistency of the smoke tells me something too.

Anyway....good luck and hope one of us gets it. Puzzles are interesting.

 

[nonickatall]

Good game....

My guess is that the car didn't have enough antifreeze in the coolant, there is a coolant connection at the top of the throttle valve, it broke due to frost and coolant was sucked in the intake, which caused the corresponding problems...

 

[Mudsport96]

Coolant reservoir leaking and running down into the airbox....

 

[SpareParts]

Im going to guess you show us a Diesel fuel can.

 

[OR VietVet]

According to my military time figures, we should have known the answer by 1400 PST or 2 p.m. for the non military. I wonder what happened?

 

[Mudsport96]

I use the 24 hour clock most of the time as well, and was wondering when the update was coming.

 

[Doubeleive]

The subject: 2005 Yukon Denali...for those that dont know....that means factory 6.0 and AWD.
Short background: Yukon has been sitting in drive for an extended period of time.
Symptoms: Hard to start, Blowing major white smoke, Reduced Engine Power on the DIC, wont get to normal idle speed, idles erratically.

I suspected bad gas so I threw in some octane booster, 4 gals of new 87 octane and some HEET. Didnt fix anything.

Ill take all guesses as to the cause of this mess until 10/26/23 1700 EST before I post pic of the cause.

Ill give you 3 clues. (1) Its not a bad battery (2) There are no fuel leaks (3) I dont live in the City.

 

[strutaeng]

This is like playing the lottery! LOL

My luck sucks, so I don't buy Lotto tickets.

What does your scanner/magic eightball say?

 

[TollKeeper]

PCV Valve.. and yes these have them.

 

[OR VietVet]

It's the next game....figuring out if we have been left hanging. @rockola1971, you can go back to post #1 and top right, click on 3 dots and edit thread as "unsolved", if you so choose.

 

[B-train]

Since the answer hasn't arrived yet.....

Based on the clues I instantly went for some type of coolant consumption based on the white smoke - but we can't smell through this site yet, so I can't be for sure. Throttle body or head gasket seeping?

The reduced power on DIC could also lend to an electronic failure caused by a rodent? Maybe the mass airflow sensor, throttle body wiring, or injectors themselves.

I'd like a pic of the engine compartment and a video of the run.

But, as @OR VietVet said, puzzles are fun! Good game!

 

[nonickatall]

I guess he was hoping that he finds the problem before us and before 10/26/23 1700 EST..

But he not succeed yet..

 

[Ibustbravo]

Ok.. This hasn't been answered yet so I'm giving it a shot.

hard to start?
Fouled plugs and or mechanically gapped plugs
Chugging white smoke??
Coolant leak in the combustion chamber...
Reduced engine power?
This is due to the other obvious signs, by design
No idle?
Large vacuum leak.. or combustion chamber leak.. hence the smoke..

 

[the 18th letter]

Maybe whatever was living in there ate him.

 

[tooleyondeck]

...bird nest

 

[nonickatall]

Burning alligator on the exhaust, which bites, in pain, in the fuel rail.

 

[nonickatall]

@rockola1971
Get in touch with us, before we come up with the absurd theory, that aliens kidnapped you, because you uncovered secret design features of the GMT 800, which is actually a spaceship for the day of apocalypse.