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ChevyTuff

Rough Idle, Stalling, White Crust On Spark Plugs

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My truck is a 2013 GMC Sierra 1500 SLE with 5.3L

 

I forgot to gas up when I was in town last week, and was almost completely out of gas. I pulled into a small town just off the interstate, and found a small un-attended fuel station and filled up the tank. The next time I went to town, about 60 miles, I noticed my GMC Sierra was idling very rough and stalling at lower speeds. When I got back home, it was still running rough, so I pulled the driver's side front spark plug and noticed it was all crusted over with some white colored junk like ash. (Photo) I'm hoping I can fill my tank with good fuel and the problem will go away. I am buying new spark plugs today.

I know there are some really smart guys on here. Any input here would be very helpful. 

 

Screen Shot 2021-02-19 at 7.49.48 AM.png

Edited by ChevyTuff
Correction

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1 hour ago, ChevyTuff said:

My truck is a 2013 GMC Sierra 1500 SLE with 5.3L

 

I forgot to gas up when I was in town last week, and was almost completely out of gas. I pulled into a small town just off the interstate, and found a small un-attended fuel station and filled up the tank. The next time I went to town, about 60 miles, I noticed my GMC Sierra was idling very rough and stalling at lower speeds. When I got back home, it was still running rough, so I pulled the driver's side front spark plug and noticed it was all crusted over with some white colored junk like ash. (Photo) I'm hoping I can fill my tank with good fuel and the problem will go away. I am buying new spark plugs today.

I know there are some really smart guys on here. Any input here would be very helpful. 

 

Screen Shot 2021-02-19 at 7.49.48 AM.png

I'm no tech and didn't stay at a holiday inn last night ? but i'm pretty sure white crusty's on the plug denotes either it running to hot or possibly oil being burned in the combustion chamber.

 

We have a few techs on here that can hopefully give you proper help.

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3 hours ago, ChevyTuff said:

My truck is a 2013 GMC Sierra 1500 SLE with 5.3L

 

I forgot to gas up when I was in town last week, and was almost completely out of gas. I pulled into a small town just off the interstate, and found a small un-attended fuel station and filled up the tank. The next time I went to town, about 60 miles, I noticed my GMC Sierra was idling very rough and stalling at lower speeds. When I got back home, it was still running rough, so I pulled the driver's side front spark plug and noticed it was all crusted over with some white colored junk like ash. (Photo) I'm hoping I can fill my tank with good fuel and the problem will go away. I am buying new spark plugs today.

I know there are some really smart guys on here. Any input here would be very helpful. 

 

Screen Shot 2021-02-19 at 7.49.48 AM.png

It appears that the plugs have been running to hot with the white ash. Bad fuel or gas additives can cause this as the computer will go to a lean operation and adjust timing due to the bad fuel or a fuel additive was added as additives will make your engine chambers run hot to burn off deposits that's how they work. But yes your on the right track by putting new plugs in and burn that fuel out of the tank before putting in fresh good fuel chances are after your burn threw that gas and putting in good fuel you may have to replace again or at least check them.

Edited by Silverado4x4

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1 hour ago, It's Tim said:

Coolant.

I would tend to agree, but let's wait to hear back from the OP about his coolant level.

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That's oil on the plug.

 

Cylinder 1 is a AFM/DoD cylinder. I bet if you pulled cylinder 7 on that same bank it will have similar whiteness to it and cylinder 3 and 5 will be more black/tan looking.

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