03 Yukon xl 1500 (vin z) stutters around 4k rpm and randomly shuts off

[Jsmarr123]

The guy I bought it from didn’t know either, had it 6 months he said, believe it to be an old company vehicle but not sure, it definitely doesn’t run like it’s pushing 300k

 

[Doubeleive]

I don't think there is any wiring correlation from the radio to the flex fuel sensor, but when you cut wires on the lan bus with the battery connected it's never a good idea.
I would take the time and get a meter and check each and every fuse.

 

[Jsmarr123]

Thanks for the advice that was on the list tomorrow after work, once it shuts off it’s kind of hard to get started back

 

[Jsmarr123]

I don't think there is any wiring correlation from the radio to the flex fuel sensor, but when you cut wires on the lan bus with the battery connected it's never a good idea.
I would take the time and get a meter and check each and every fuse.

Update, it shut off again today I smacked the fuel tank hard and since has run fine since. Ordered new fuel pump

 

[Fless]

If you haven't been able to look at the fuel pump you may want to have a new lock ring on hand to have when you replace the pump.

 

[Jsmarr123]

If you haven't been able to look at the fuel pump you may want to have a new lock ring on hand to have when you replace the pump.

Ok thank you, I’ll check into that, going to cut a hole in the floor I’m out of town working and don’t think the hotel would appreciate me dropping a tank in the parking lot also it would be quite challenging by myself

 

[calsdad]

I don't have time right now to write out the whole story - but I had a similar problem with my 2003 Suburban 2500. All sorts of codes , fuel pump, cam position sensor, crank position sensor, ignition codes, engine shutting off - the whole thing.

First problem I found was that mice had gotten into the wiring directly under the fuse box in the engine compartment. I had at least 4 wires completely severed and 10 more that were showing bare copper. Spent a Sunday carefully soldering and heat shrinking the wires back together to fix that problem. That still didn't stop the codes though. I kept getting them. I had a sneaking suspicion that the ECM (engine computer) was bad , but had a number of people tell me "they don't go bad" - so I kept discounting that gut feeling.

After a couple of months of screwing with it - I finally replaced the ECM with an exchange unit - and that finally fixed the problem.

I would also add - the problem on my truck appeared to be due to heat as it would run for a short time really well when the engine compartment was cold. As soon as things heated up - that's when the trouble started.

You sound like you might have a similar problem - what with a whole bunch of different codes showing.

Just my 2 cents.........

 

[calsdad]

Ok thank you, I’ll check into that, going to cut a hole in the floor I’m out of town working and don’t think the hotel would appreciate me dropping a tank in the parking lot also it would be quite challenging by myself

Dropping the tank is easy - I did it on my Suburban and it was way easier than I imagined it would be. Just make sure to somehow drain as much gas out of the tank as possible. If it was me I would not cut a hole in the floor.