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Brand new Sierra 5.3 CEL flashing

Andyh1
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Andyh1 Enthusiast

Andyh1

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Hi guys, first post on this platform. Purchased my first GMC truck, hell my first truck ever, and loving this rig. 

Elevation trim with the 5. 3 V8 engine. 

Currently sitting at around 1180 miles. I changed the oil at 1050 miles with mobile 1 0w20 (8qts.)

Today while highway cruising, I Noticed the engine icon started to flash for maybe 10-20 seconds  on /off and then it went away. 

 

From what I've gathered could this be a cylinder misfire this early on? 

I will pull codes tomorrow if any but again, this happened so quick and it never came back. 

I did not feel any loss of power or anything unusual. 

Oil level is good also... Should I have the dealer check it out? 

Any others with similar scenario?

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Andyh1
Andyh1

I finished my 200 mile round trip this morning. No problems at all, truck is strong. On a lighter side, my girls absolutely love this rig and we're super excited about the new baby hens 4 bared rocks

Colossus
Colossus

Good deal.  well here's to hoping. 

Michael Ruch
Michael Ruch

Yeah I’m just concerned with it since it happened again after 200 miles.    And yeah mine was 11 secs according to the scan tool. It’s was running fine. And bam just started to flash just cr

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Andyh1 Enthusiast

Andyh1

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1 hour ago, Andyh1 said:

Hi guys, first post on this platform. Purchased my first GMC truck, hell my first truck ever, and loving this rig. 

Elevation trim with the 5. 3 V8 engine. 

Currently sitting at around 1180 miles. I changed the oil at 1050 miles with mobile 1 0w20 (8qts.)

Today while highway cruising, I Noticed the engine icon started to flash for maybe 10-20 seconds  on /off and then it went away. 

 

From what I've gathered could this be a cylinder misfire this early on? 

I will pull codes tomorrow if any but again, this happened so quick and it never came back. 

I did not feel any loss of power or anything unusual. 

Oil level is good also... Should I have the dealer check it out? 

Any others with similar scenario?

Ran the scanner and it shows a code P0300... taking this thing into the dealer for them to take a look. Its too new for a misfire to happen. 

Colossus Senior Enthusiast

Colossus

Posted
Posted

Some new things are known to fail.  Hell go visit your local Toyota dealer service bay and you'll see new vehicles get towed in from time to time.  Even they are not perfect.  <sigh> but sure is frustrating no doubt.  Let us know what happens. 

Andyh1 Enthusiast

Andyh1

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Just don't erase the codes. 
I kept then codes and the dealer got to see them.

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Andyh1 Enthusiast

Andyh1

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Some new things are known to fail.  Hell go visit your local Toyota dealer service bay and you'll see new vehicles get towed in from time to time.  Even they are not perfect.  but sure is frustrating no doubt.  Let us know what happens. 
I totally get it... Not hating at all, I love this rig

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Andyh1 Enthusiast

Andyh1

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Ok here is the update:
dealer kept the truck overnight and ran tests but the P0300 never cane back.
May have been an isolated incident since the computer cleared the code itself, who knows.
Westpoint Houston did a good job I feel, and the truck is running strong.

Taking a trip with the kids in the am near Austin to pick up chickens for our coop.
I'll keep my eye on it but running as it should now.






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jnissen Enthusiast

jnissen

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Posted
Ok here is the update:
dealer kept the truck overnight and ran tests but the P0300 never cane back.
May have been an isolated incident since the computer cleared the code itself, who knows.
Westpoint Houston did a good job I feel, and the truck is running strong.

Taking a trip with the kids in the am near Austin to pick up chickens for our coop.
I'll keep my eye on it but running as it should now.






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Ok you got my interest... how many chickens?
Andyh1 Enthusiast

Andyh1

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Ok you got my interest... how many chickens?
I just picked up nine hens [emoji4]

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Andyh1 Enthusiast

Andyh1

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I finished my 200 mile round trip this morning. No problems at all, truck is strong.
On a lighter side, my girls absolutely love this rig and we're super excited about the new baby hens

4 bared rocks
2 australoprs
3 cochins

eb6f2534d1718bec473b02e7c4b4ede1.jpg67319bb65a2478756650ea29b3913c82.jpg

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Andyh1 Enthusiast

Andyh1

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Did you have any outcome from this? I got my oil changed at 3k miles 2020 5.3 and right after that I’ve had the p0300 code pop up 2 times now 

I don't have enough of a trail to follow... It cold be a coincidence but I had just changed my oil at 1150 miles and it happened exactly 3 days later, similar to you. . Same code P0300...

The dealer could not duplicate it and the vehicle computer cleared the code. They ran tests on it but the code never came back. I recall the engine icon flashed for maybe 10 seconds and it went away but definitely threw that code.

I'll keep my eye on it.

 

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Michael Ruch Enthusiast

Michael Ruch

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Posted (edited)

Yeah I’m just concerned with it since it happened again after 200 miles. 

 

And yeah mine was 11 secs according to the scan tool. It’s was running fine. And bam just started to flash just cruising. 

 

I wonder if its a soft ware problem 

Edited by Michael Ruch
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Andyh1 Enthusiast

Andyh1

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Yeah I’m just concerned with it since it happened again after 200 miles. 
 
And yeah mine was 11 secs according to the scan tool. It’s was running fine. And bam just started to flash just cruising. 
 
I wonder if its a soft ware problem 
Hmmm. It could be software, true.
Todays morning trip (200 miles) was important to me to see if it came back. Fortunately, not.

Did you check oil level, I had read that too much oil may be an indicator. I may be 1/4 of a quarter over.

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