2006 Yukon XL 2500 6.0L dies/stutters at cruising speed randomly

[jmlhd7]

I've got an 2006 Yukon XL 2500 with the 6.0L. Since the week before christmas I've been having an intermittent stalling issue with the engine. My wife was driving it and took off at an intersection and said that it died on her and she pulled over, turned it off and it immediately restarted.

Its normally my boat towing vehicle so it sits a majority of the time, so I started driving it to see if the issue would present itself again. For me what happened once every couple days is that I would seem like the engine would cut off for a split second and you'd feel a shutter/jerk, and then it'd pick back up again like nothing happened. Seemed to do it around 45-65 mph range.

Ended up lending the car to a buddy this past week and over the weekend if actually did the same thing as it did for my wife, completely died around 45mph, but still had dash power and everything and when he got to the side of the road, he turned it off and it started right back up again.

No check engine codes or check engine lights have ever come on. The only thing on the dash is a service airbag warning that I haven't gotten scanned yet, but none of this engine issue was noticeably before that light came on, so not sure if they are related or not.

I was kind of thinking fuel issue, or maybe plugs/wires, but not I'm wondering if its a bad ground connection. I have a battery that is only like 6 months old so I think that's fine. I don't want to just start throwing parts at it but i'm also not sure where to check. Any insight/thoughts would be appreciated.

 

[Bigburb3500]

Check the MAF. Had similar issues on mine and it was the MAF couldn’t figure out the right fuel/air ratio to keep the truck running.

 

[Fless]

What history can you share about the Yukon? How long have you owned it, what maintenance has been done, etc.

Do a standard fuel pressure test (KOEO as directed in service data); if it fails you may want to change or diagnose the fuel pump. Consider monitoring it using a long hose and taping the gauge to the windshield. Post up the values you are reading.

I would also recommend a voltage drop test for both main cables from the battery (+ to starter, and - to engine and body).

This is low probability, but carefully pull the connectors from the ECM and check for corrosion and pin fitment. The gaskets on those can leak water into the connectors.

 

[Scottydoggs]

if the tach has ever dropped to zero before it dies out, id suspect the crank sensor is bad.

 

[Fless]

Lots of data to check and verify, and start crossing off suspected causes. A general "physical" might show some particular piece of data that doesn't make sense.

 

[rockola1971]

Fuel filter (If equipped) > Fuel Pump. Check that fuel pressure. Fuel pump sounding kinda gritty?

 

[jmlhd7]

if the tach has ever dropped to zero before it dies out, id suspect the crank sensor is bad.

It happened to me again at the boat ramp this weekend. Truck was still physically running but tach was buried at zero for 15-30 seconds before it died. Hoping this is the answer instead of the fuel pump.

 

[Bigburb3500]

Keep us posted!

 

[Doubeleive]

I've got an 2006 Yukon XL 2500 with the 6.0L. Since the week before christmas I've been having an intermittent stalling issue with the engine. My wife was driving it and took off at an intersection and said that it died on her and she pulled over, turned it off and it immediately restarted.

Its normally my boat towing vehicle so it sits a majority of the time, so I started driving it to see if the issue would present itself again. For me what happened once every couple days is that I would seem like the engine would cut off for a split second and you'd feel a shutter/jerk, and then it'd pick back up again like nothing happened. Seemed to do it around 45-65 mph range.

Ended up lending the car to a buddy this past week and over the weekend if actually did the same thing as it did for my wife, completely died around 45mph, but still had dash power and everything and when he got to the side of the road, he turned it off and it started right back up again.

No check engine codes or check engine lights have ever come on. The only thing on the dash is a service airbag warning that I haven't gotten scanned yet, but none of this engine issue was noticeably before that light came on, so not sure if they are related or not.

I was kind of thinking fuel issue, or maybe plugs/wires, but not I'm wondering if its a bad ground connection. I have a battery that is only like 6 months old so I think that's fine. I don't want to just start throwing parts at it but i'm also not sure where to check. Any insight/thoughts would be appreciated.

start at the battery, check cables and grounds.... that's the first place to start looking.
even though the tach dropped 1st, verify fuel pressure with a mechanical gauge.

 

[jmlhd7]

start at the battery, check cables and grounds.... that's the first place to start looking.
even though the tach dropped 1st, verify fuel pressure with a mechanical gauge.

Battery cables and grounds look good. Got a mechanical gauge and planning on checking the pressure this weekend. Drove it this morning for about 40 min without issue. I did clean the MAF and replaced the MAP sensor this past weekend. What pressures should I be looking at on the fuel pump when checking with the gauge? Thanks!

 

[Doubeleive]

Battery cables and grounds look good. Got a mechanical gauge and planning on checking the pressure this weekend. Drove it this morning for about 40 min without issue. I did clean the MAF and replaced the MAP sensor this past weekend. What pressures should I be looking at on the fuel pump when checking with the gauge? Thanks!

on the gmt800's it should be 50+ running

 

[jmlhd7]

on the gmt800's it should be 50+ running

alright, I had a short one and hooked it up last night but it was 60 psi at idle in the garage. waiting to get a longer hose and tape to the windshield while driving to see if it changes/drops much.

 

[Doubeleive]

alright, I had a short one and hooked it up last night but it was 60 psi at idle in the garage. waiting to get a longer hose and tape to the windshield while driving to see if it changes/drops much.

60 is healthy, but ya monitor it just to see if it is crapping out

 

[Bigburb3500]

Battery cables and grounds look good. Got a mechanical gauge and planning on checking the pressure this weekend. Drove it this morning for about 40 min without issue. I did clean the MAF and replaced the MAP sensor this past weekend. What pressures should I be looking at on the fuel pump when checking with the gauge? Thanks!

I had a bad MAF on mine as well. Whenever it would rain or super high humidity the engine would cut out.

 

[Fless]

Start at the link below but use the links at the top of the browser to move to the correct section for your SUV.

Fuel System Diagnosis — 2006 GMC Yukon XL 2500 4WD V8-6.0L VIN N Service Manual | Operation CHARM

Detailed repair manual for the 2006 GMC Yukon XL 2500 4WD V8-6.0L VIN N.

charm.li

 

[jmlhd7]

I've driven it for 3 days straight now after cleaning the MAF and replacing the MAP and haven't had the dying/stutter happen again, but still driving around with a scanner hooked up to try to catch any code. supposed to get a long fuel gauge today and will drive with that too. Noticed today that after the engine was warm my idle rpms were down almost near 300 RPMs on the gauge. Didn't sound like it was dying or starving, but I honestly don't remember it normally being that low on the gauge.

 

[rockola1971]

Verify the ACTUAL idle rpm reported on the scanner. Never trust the instrument cluster when troubleshooting. These clusters of this era arent exactly the most dependable in the world.

 

[jmlhd7]

Verify the ACTUAL idle rpm reported on the scanner. Never trust the instrument cluster when troubleshooting. These clusters of this era arent exactly the most dependable in the world.

I have an OBD scanner but it doesn't do live reads. Anything you'd recommend to verify this? Not trying to break the bank but would like to get this figured out.

 

[rockola1971]

I have an OBD scanner but it doesn't do live reads. Anything you'd recommend to verify this? Not trying to break the bank but would like to get this figured out.

What unit are you using? Just about any basic scanner will show RPM, Fuel trims, ignition advance. etc.

 

[jmlhd7]

Alright, an update, but with limited testing. About 10 days ago I cleaned the MAF sensor and the MAP. When pulling the MAP sensor I noticed the o-ring was damaged. Instead of just replacing the O-ring I just purchased a new OEM Map sensor and installed it. Since then I've driven the yukon a total of 4 trips, probaby 60 miles total and have not had it die or any of the shutters/jerks at driving speed.

I have also hooked up a fuel pressure gauge and taped it to my windshield for one drive and it was consistently at 60 psi while driving.

Today I got a new scanner that does live graphs of RPMs and it idle (engine was cold, just started to test it) my gauge tach dropped to roughly 300rpm, but my scanner was reading 650ish RPM at idle.

My plan is to continue driving it more with a fuel gauge attached to see if there are any fluctuations and I'm also going to keep driving it with a scanner hooked up to see if I get any pending codes if it happens to stutter/jerk or die.

I have a hard time believing that MAF/MAP sensor would be the root cause of my issues, so I'm assuming it will mess up again, but it was happening pretty frequently before cleaning those sensors.

On a different note, what do I do about the gauge tach being off? I feel like that is a recent development with me trying to track down this random issue as I don't remember it being that low for the first year of ownership.

My initial thought is its still most like the crank position sensor, but also it would just be a guess. I'd like to have some proof before changing more parts.