Hello -



On my way home from work today, my CEL flashed a few times slowly, then went away. It did this another time or 2, before permanently turning off. I continued driving home (was about 10 mins away) and stopped by my parents to use my dad'* OBD2. It said Cylinder 5 misfire detected, P0305.



I guess my question is, if the CEL stopped blinking and does not come back on, how big of an issue is this potentially? Like if the detected misfire were to continue, would the CEL continue to blink? The fact that it is no longer on (as of when I got home at least), am I good for now?

Whatever the problem is probably didn't fix itself.

In the older days, a misfire just had the engine run worse, and if left long enough would cause bigger issues.

Here in modern times, a misfire means that fuel didn't get burned completely, therefore it goes down stream and burns the rest of the way in the catalytic converter. Too much fuel doing this melts the core of the catalytic converter. The catalytic converter is designed to burn the leftovers, but not the main course. That'* why the check engine light will flash for severe misfires.

Is this on the 2015 Silverado 1500 5.3 ?

2016 Silverado 1500 5.3

So basically the misfire (for now at least) was just a 1-time occurrence, not a constant misfire continuing to happen?

I would diag this further.
Could be faulty ignition coil(3800'* would fail when hot, but fine when cold) Swap it with a neighbor coil. If misfires again, the misfire will move to another cylinder.
Faulty ignition boot to spark plug
Something clogged injector momentarily causing lack of fuel flow.

Open the hood and visually inspect everything, Could have a rat infestation.
I could speculate allll day.

I can't tell from here, but it probably didn't fix itself. I'd diagnose it if it were me.

One things for certain. Never load up an engine that is misfiring and flashing the check engine light.