Intermittent shut down issue

[John Bragg]

Hello all! So my 2003 Yukon XL is having a temper tantrum. For a while now I have been having random engine shut downs. No check engine light, and actually no lights at all except the battery light. I was thinking it was a fuel issue, however that seems to not be the case. I was wondering if possibly it's a passlock issue, however like I said no lights come on in the dash. But what is leading me to wonder about the passlock is the fact that the engine will just **** down kind of like the injectors were shut off. Then attempts to start the engine again occasionally will start and run again. Now that scenario is becoming less and less often not it will crank but not start. Occasionally sounds like it's gonna start then immediately returns to cranking only. Then if you let it sit for a while it will just start up like nothing ever happened. I have had it towed 2 times and each time the tow truck drive said it started no problem when they got there and when it gets dropped off at the house it just starts and runs. It was like once a month, then somewhat weekly now it has become daily and multiple times daily. To the point I won't even drive it to work less than 2 miles away. Anyone have any similar issues? Anyone have any suggestions? Any info and direction would be great appreciated. I have scoured the internet for many hours and haven't found a whole **** of a lot. Thank you in advance.

 

[treehan77]

Fuel pump? Next time it doesn’t start, **** on the tank a little a see if it starts.

 

[John Bragg]

I replaced the fuel pump a couple years ago maybe 3 years ago, I can hear it prime and I also did try that just for ***** and giggles unfortunately didn't help. Thank you for the suggestion that is what makes these forums great lots of great minds coming together to help one another

 

[OR VietVet]

WAG, check fuel pump pressure from KOEO, cranking, running and how far does it bleed off when engine is shut off.

Next WAG is cam and crank sensors. Some people here would do one or the other but I always recommend both.

How old are ignition components?

 

[John Bragg]

I have replaced the crank sensor on advise from a family friend when I was having reduced engine power issues like crazy. Plugs are wires are less than 3 years old. I'll definitely check the fuel pressures as well I did put a whole new unit in the tank about 3 years ago as well as all new fuel lines. Thank you for the input and suggestions it's much appreciated.

 

[Tonyrodz]

I had the EXACT same issue in my 03. Do you drive uphill, or go down hill when it happens? Or even a slight incline does it? Turned out my fuel filter was so clogged that the sediment would move going uphill or down, and would clog the fuel line internally, thereby choking off any fuel flow, shutting it down. Of course it would start after sitting. Guess the sediment would flatten out, opening the line internally. How old is your fuel filter? Swap it out.

 

[John Bragg]

Unfortunately there is no consistency in when, where, how, or what the circumstances are when it happens. Hot, cold, idle, highway speeds, it is completely random. This weekend in fact, not that I have stopped driving it completely, I stared it up to keep the battery charged and the fluids moving it ran a out 15 minutes then died. Would t restart after several attempts. Let it sit for about 15 minutes then tried it again it started and died again after about 5 minutes. Wouldn't start again. I gave up. As far as the fuel filter goes I put one in less than a month ago. In the last about 4 years it has had the entire fuel system replaced short of the injectors. Thanks for the insight tho i do appreciate it.

 

[Bill 1960]

Keep a spark tester and fuel pressure gauge in the truck at all times so you’ll be ready to isolate which system is failing.

When my fuel pump was acting up I just duct taped the gage to the windshield where I could see it and drove it that way a couple of days.

 

[Tonyrodz]

Unfortunately there is no consistency in when, where, how, or what the circumstances are when it happens. Hot, cold, idle, highway speeds, it is completely random. This weekend in fact, not that I have stopped driving it completely, I stared it up to keep the battery charged and the fluids moving it ran a out 15 minutes then died. Would t restart after several attempts. Let it sit for about 15 minutes then tried it again it started and died again after about 5 minutes. Wouldn't start again. I gave up. As far as the fuel filter goes I put one in less than a month ago. In the last about 4 years it has had the entire fuel system replaced short of the injectors. Thanks for the insight tho i do appreciate it.

Gave it a shot. Sorry. I hate random issues, it's like trying to find where a leak in your roof is coming from lol. Hope that makes sense.

 

[Doubeleive]

clean up the maf and throttle body also, just because....in addition to the other suspects a dirty faulty intake can also be a problem.