My GMC Sierra elevation had a flashing check engine

[Pablo Villagomez]

My 2018 GMC Sierra had check engine light flash several times but I went away and haven’t had it do it again, I didn’t notice a difference while driving and the light flashing. Anyone else have had this happen? 
Also it just hit 30xxx miles the day it flashed 

[CamGTP]

Flashing normally means possible catalyst damage, aka a misfire is the normal culprit.

 

You could try to scan the engine computer to see if there is a history code of the problem. That is all we could tell you at this point.

[Pablo Villagomez]

The truck is still fairly new, would the warranty cover? 

[JimCost2014]

34 minutes ago, Pablo Villagomez said:

The truck is still fairly new, would the warranty cover? 

When did you buy/when was it put into service? Sounds like you are good on miles as far as the 36/36000 warranty. 

[Pablo Villagomez]

I bought it brand new, I had a lift and bigger tires added to it. I hear that the the warranty can be voided since it wasn’t done by the dealership.

[Pablo Villagomez]

17 minutes ago, JimCost2014 said:

When did you buy/when was it put into service? Sounds like you are good on miles as far as the 36/36000 warranty. 

I bought it brand new, I had a lift and bigger tires added to it. I hear that the the warranty can be voided since it wasn’t done by the dealership.

[JimCost2014]

30 minutes ago, Pablo Villagomez said:

I bought it brand new, I had a lift and bigger tires added to it. I hear that the the warranty can be voided since it wasn’t done by the dealership.

Still would try, nothing to lose, especially if this can not be traced back to the lift.

Edited August 25, 2020 by JimCost2014

[Pablo Villagomez]

1 minute ago, JimCost2014 said:

Still would try, nothing to loose, especially if this can not be traced back to the lift.

Wouldn’t think this could be traced back to the lift, but I wouldn’t know. Do you think it could be? 

[JimCost2014]

13 minutes ago, Pablo Villagomez said:

Wouldn’t think this could be traced back to the lift, but I wouldn’t know. Do you think it could be? 

To be very honest, I have no idea. Had a flashing CEL in my 16 when it broke a push rod, so not a lot of experience with this problem.

 

I would take it in, and have them run a scanner for codes, there could multiple reasons why it happened, and they may find nothing since it sounds like it is running good again.