I hate intermittent problems .
 

I get them at work all the time , customer comes in telling me that on Tuesdays, when it rains and the rolling stones is playing on the radio at 9:37 pm their car makes a funny noise . I am limited to only a test drive, check codes, look for the obvious, and a lot of times, not much you can really do until I catch it in the act, or it finally goes kaput .
We just got back from a camping trip in the Pocono mountains . Beautiful place .
Towed heavy all the way there. Last night, we went up to check out a few lakes , and on the way back, cruising at about 45 mph no load, no trailer on, all of a sudden, feels like I have no power . I start pushing on the gas, and sure enough, truck is barely running, All gauges look normal, no check engine light, but battery light is on. Voltage gauge shows better than 14 volts . Turn down radio, and tell family that , oh crap, we are 500 miles from home, and are breaking down in the middle of no where in the dark . Truck is still running but when I push on gas, truck starts knocking and making all sorts of horrible noises that I have never heard this truck make before.
I coast a bit while idling till I can find a safe place to pull over . Shut down, open hood, check all fluids, check for codes, look for any misplaced wiring, or damaged belts, hoses , foreign debris , and nothing, nada . It was not in limp mode . Attempt to re-start truck and it fires right up like normal, and runs perfect for the entire 40 minute drive all the way back to our campsite .
Came home today, 5 hour drive towing 10k in 90 deg, heat, and the thing never skipped a beat .
I am towing 1200 miles in a month from now , and I have lost some confidence in my setup . Although I was happy to make it home, I would have rather just broke down, and known exactly what was wrong . When is it going to happen again? You can be sure it will not be anywhere near home.
I suspect my tuner is on the fritz, and I was looking for a good excuse to upgrade anyhow , but there really is no way of knowing . A quick google search shows some similar failures in high heat situations .

My 04 GMC 2500HD made some ungodly noise on a long downhill on a mountain highway.
Shifted in to neutral, noise was still there.
Stepped on the gas to see if the noise was engine rpm related, noise goes away and hasn't returned....
Stopped and checked belts and fluids and anything obvious to no avail.
How do you diagnose that????

Just don't go downhill and you'll be fine. :)

Radio related?

Which vehicle?

Think he means performance tuner.

Doh!

Computerization.

Yep. Happened to me. Pull over, tune out the Stones and let the Fm cool out with some Yanni or George Winston. Too much Stones will overheat the balls in your Wasserman bearings . If you're in a hurry you can ask someone in a rest stop to blow on your hot balls, but you might be better off just waiting for them to cool.

Fuel pump?

Hah! I'm a software developer on a massive application that has spawned 7 satellite applications. 10 years of continuous work by a team of 10-15, and not a single person has been here more than 4 years. We are a hard core test driven development(TDD) shop (you don't write code without writing a test that proves it works, and the tests are run continuously so that if someone breaks something, you know about it right away). Even in that environment, we run into 'automagical' stuff all the time. "Wait....how the hell did THAT just happen?!"

what stones song?

If it was in the 04 duramax in your sig most likely chaffed harness at fuel injection control module or broken wire to either of the two rearmost injectors on passenger side. Computer sees a momentary fault and will shut down a full bank of injectors until ignition is cycled. Broken inj wires will leave a code, shorted wires at ficm will not always.

It was indeed my lb7 D max .
Thanks for the tip, I did find also find a TSB about this , and this is most likely the culprit. I am going to take it to work today and check the harness over real good .
Up till this , hands down has been the most reliable vehicle I have ever owned.

Try Monkey Man. Charlie really keeps the whole band together...

My Bimmer has had an intermittent fast blinker for years. I've replaced all the bulbs, cleaned all the grounds, read all the forums posts on what might be the problem, and it's still intermittent blinking fast. No idea why anymore, and at 215Kmi, I no longer care -- the turn signals all blink, they just blink fast. SMH.

I worked on a project a few years ago, like HardDrive, that had started out as a little single-computer thing, and had developed over a few years into a monstrosity. When I was working there, a single customer installation had ~100 separate networked computers, many of which were running code that we didn't own or control or even have insight into. Like HardDrive, a "senior" employee of that company had been around for about 2-3 years, so corporate knowledge was mediocre. As one of the integration/testing types, my job was to push on the system until it broke, and let me tell you, we found some bizarre things. We once found an easter egg where a polar bear wandered across the screen. I guess that'd be normal in a video game or something, but this was in software that was supposed to be delivered to the US Navy, for use on submarines, haha.

Working that job became an exercise in documenting exactly what we had done, so we could explain it to the developers. "No, seriously, you have to watch this: when I push this totally unrelated button over here, after having done that sequence of other totally unrelated things, that machine over there turns into an ice cream sandwich. But if we do it in this other order, everything works fine!" There's nothing so much fun as duplicating something insane and watching the engineers go crazy, hahaha.

WELCOME to my world. Petty ****.... all day long