2011 Yukon flashing CEL ?

[Dan2002]

I recently found a problem with my vehicle. It's a 2011 gmc Yukon xl with around 175,000 miles.

Had it for about 3 years. One day I was driving down the highway. And as soon as I hit 60,mph it starts to flash the Check engine light and you can feel the power loss as if it's missfiring. It'll shake a little and then go back to normal as soon as I let go of the gas.

I have checked for codes and once it gave me misfiring cylinder 3 and random missfire. P0300

Now it only gives me random missfiring

I went ahead and change all new plugs. Cables and even got a whole new set of ignition coils. But that didn't seem to help at all.

It still is doing the same thing. At 60mph

Otherwise at other speeds it drives just fine.

 

[Dan2002]

I recently found a problem with my vehicle. It's a 2011 gmc Yukon xl with around 175,000 miles.

Had it for about 3 years. One day I was driving down the highway. And as soon as I hit 60,mph it starts to flash the Check engine light and you can feel the power loss as if it's missfiring. It'll shake a little and then go back to normal as soon as I let go of the gas.

I have checked for codes and once it gave me misfiring cylinder 3 and random missfire. P0300

Now it only gives me random missfiring

I went ahead and change all new plugs. Cables and even got a whole new set of ignition coils. But that didn't seem to help at all.

It still is doing the same thing. At 60mph

Otherwise at other speeds it drives just fine.

Checked for fuel pressure it's at 50 psi without starting and while running it's around 55 psi

 

[Dan2002]

For anyone that comes along with the same issues. I got it fixed by doing a Crankshaft relearn procedure. With a dealer level scanner.

 

[Geotrash]

For anyone that comes along with the same issues. I got it fixed by doing a Crankshaft relearn procedure. With a dealer level scanner.

Thanks for following up with this. Very helpful for all of us to have your resolution here. Glad you got it sorted!

 

[swathdiver]

Checked for fuel pressure it's at 50 psi without starting and while running it's around 55 psi

Hopefully that gauge is off. Your running pressure is supposed to be 43.5 psi. I wonder if the balancer is starting to move on the crankshaft?

 

[Geotrash]

Hopefully that gauge is off. Your running pressure is supposed to be 43.5 psi. I wonder if the balancer is starting to move on the crankshaft?

That's a good point, James. If this problem comes back, I'd be inclined to suspect that the pressure regulator on the fuel pump is starting to go. I had similar symptoms in my 2007 when the pump started to go south.

 

[Dan2002]

That's a good point, James. If this problem comes back, I'd be inclined to suspect that the pressure regulator on the fuel pump is starting to go. I had similar symptoms in my 2007 when the pump started to go south.

Thank you guys for the heads up. I am planning on a little vacation trip on April and I might as well get the fuel pump replaced just in case, I wouldn't want to get stuck somewhere