New problem with this 2012 Yukon XL 1500 Denali 6.2L. I really hate this truck! GREMLIN is back

[testdepth]

Did you replace the pick up sock in the fuel tank. It's a little nylon sock that goes over the pickup in the fuel tank. I've had cars before or trash gets into the gas tank and accumulates around that fuel pick up sock and chokes the flow of gasoline off. It causes symptoms exactly like what you have explained. In a run for a while that trash gets around the sock and then it cuts off. After you let the truck set for a while it'll start back up but then after you let it run for a little bit it'll cut right back out. Usually a new pickup sock is offered with the new pump but if it wasn't then it could be your problem. If that is the problem you need to take the gas tank off or out and totally dump it out. Clean it out real good and then put the fuel pump back in with the new clean sock. These LS engines being fuel injected running extremely high pressure. Like 58 PSI believe if I'm remembering that correctly. Any kind of blockage in that fuel system is going to cause a problem with fuel delivery. It could be a falter fuel pressure regulator, a clogged rail or that fuel sock if the gas tank is full of crap.

I've also seen sensors that will act up like that as well when they get hot. As soon as the center cools down it'll work as normal but then when it heats back up it'll shut off again. Normally the mechanics can't diagnose that because they're testing it when the sensor is cool. The technician needs to test the system when everything is it operating temperature including all the sensors then he may be able to get an accurate reading. I'm not saying any of this is definitely the problem but I have running this before and these were two problems that caused a lot of frustration.

My problem was the AFM system.

I've had this fuel tank out multiple times and never ran across any sock in it or attached to the fuel pump. May not be on my truck. Thank you for your input though.

 

[greg vess]

Every car and truck should have that pre-filter on the end of the fuel pickup. It's not a fine as micron is the actual fuel pump but it is a small enough to keep out the larger particles that get into the fuel pump. This is an essential part of the fuel system and comes on pretty much every car made. Now if the problem is in the active fuel management you need to get that hooked up to a tuner and have him deactivate that system. That goes in hand in hand with the active displacement system. A 2012 Denali with a 6.2 absolutely has a fuel sock on the end of the fuel pump. That is what they call a primary filter. It filters out all the larger contaminants before it gets to the smaller micron filter which is the secondary filter. Today's fuel injection systems are very finicky when it comes to dirt in the system. One little speck of dust or grit or grime can get the fuel injector and really throw it off. That's why it's essential it to have several filters in line to make sure nothing gets through there. Don't take my word for it do a little research. I've dealt with those kind of problems for I don't know how many years. Anywhere from boats, cars, trucks and you name it

 

[Asbestos]

Every car and truck should have that pre-filter on the end of the fuel pickup. It's not a fine as micron is the actual fuel pump but it is a small enough to keep out the larger particles that get into the fuel pump. This is an essential part of the fuel system and comes on pretty much every car made. Now if the problem is in the active fuel management you need to get that hooked up to a tuner and have him deactivate that system. That goes in hand in hand with the active displacement system. A 2012 Denali with a 6.2 absolutely has a fuel sock on the end of the fuel pump. That is what they call a primary filter. It filters out all the larger contaminants before it gets to the smaller micron filter which is the secondary filter. Today's fuel injection systems are very finicky when it comes to dirt in the system. One little speck of dust or grit or grime can get the fuel injector and really throw it off. That's why it's essential it to have several filters in line to make sure nothing gets through there. Don't take my word for it do a little research. I've dealt with those kind of problems for I don't know how many years. Anywhere from boats, cars, trucks and you name it

View attachment 9560025

Have you been reading this thread? Just curious

 

[greg vess]

Have you been reading this thread? Just curious

Negative. I just read the first few posts and threw out there some issues I found when I came across these kinds of problems before. If the problem is solved then great!

I mainly chimed in just to tell everybody that this can be corrected with a tuner if they want to get that feature deleted. I also just threw out a couple of remedies that I found that will correct these kinds of issues if people are having them. Everything can be done through a tuner like to start stop feature, the active displacement management and all those other things that can aggravate the hell out of someone. If it weren't for the problem the OP is having then it was for the benefit of others that might have an LS based engine and are experiencing the same problems.

These cars these days or something else. There's an issue with the old 99 through 2002 f bodies ( Camaros and Trans ams ) that the driver's door window and the radio would cut out the same time. You have to get up underneath the glove compartment and take out a small box and then resolder a connection that's in there. Now that is something that's completely ridiculous I don't know what is. I've had to do that on four f-bodies before. Sometimes things pick up and they have no rhyme or reason. So I just throw things out there in case someone reads the thread and might come across the same problem. 😁

 

[basstracker89]

Have you been reading this thread? Just curious

He ain'ts gots time for dat!!!........

 

[greg vess]

He ain'ts gots time for dat!!!........

Correct! I love the sound of my own voice even though I am not speaking. 🤣

 

[greg vess]

What ended up being the problem?

 

[Asbestos]

What ended up being the problem?

Everything you said fixed it

 

[greg vess]

Everything you said fixed it

Are you joking or just playing around?

 

[Asbestos]

Are you joking or just playing around?

It’s only 7 pages, Greg… and you’re the least busy of all the ODTrs.