My 7.3 has had a habit for some time of a galloping idle for 3-8 seconds when started after it has been sitting for a while (i.e. weeks). If it's been run recently, it starts right up to a smooth idle.

However, last week the problem took a turn for the worse. In deer camp, after sitting unused for only three days, it started with the galloping idle, then quit, which it hasn't done before. It did it again 4 or 5 times before starting and idling smoothly. Naturally I'm worried that it will get worse to the point that the idling smoothly part will never come about.

As best I can describe it, the engine cranks normally, fires off at the normal time, then the RPM varies from about 600-900 in a "rrrRrRrRRRMMMsilencerrrRrRrRRRMMMsilencerrrRrRrRRRMMMsilence" pattern.

I've tried to record a video of it, but it naturally hasn't done it since.

When doing the galloping idle it doesn't respond to any throttle input. Note also that the truck would do this before I installed the Hydra with PHP tunes.

Thoughts?

Oh, and because posts are more fun with pictures, and because it's on topic because the problem happened while deer hunting.....

My son with our bucks:



On our way home:

 

Sounds like a UVCH issue to me.

 

It could be dead dinos in the cold with old sticks... or glow plugs bein' lazy. Hooray for Hydra, you can go to tune 00 and that bypasses the tuner completely. What happens there?

 

The injectors are OEM but the truck has only 73,000 miles.

The dino isn't old as the truck recently did 2,000 miles to Yellowstone and back, and on driving to the ranch had been refueled in Ellensburg on Friday before the hard starting Monday morning.

The GPR is only a few weeks old per this thread, and that fixed the hard-to-start-at-all problem.

I didn't try switching to 00 on the Hydra, but the problem existed pre-Hydra. It's just that this is the first time the galloping idle problem has worsened to a quit-running rather than keep-running-and-smooth-out-to-normal event.

Another problem is that it's not very repeatable - it hasn't done it since, and probably won't again until that truck has been sitting at least a week without being run.

There's no CEL, but I don't have a way to read codes.

 

Ok. What kind of oil are you running and how cold has it been.

 

Delo 15W-40, changed 200 miles ago, the nights got to mid '30's at the lowest.

 

5w40 and check your GPR, and GP's, also injector seals, My truck DID the same thing

 

mainly due to the GP's not firing up was my issue, did the same exact thing you described...

 

Mine was the wrong type of oil. I'm not sure which type to run in colder temps (I forgot) but I switched and never had the problem again, I do switch back in the spring.

 

E-burg, eh? I don't suppose you'd have a chance to happen by Wenatchee. If this was an emergency, I'd jump into Stingy and bring the AE. Leaving the pile of lumber unfinished in the garage would get the wife after me if it wasn't an emergency.

Synthetic is 5-40... that's all I use.

 

Sounds like the romps to me.
Next cold start after sitting for a while...try jumping across the glow plug relay terminals (to manually heat the cylinders) and see if the issue returns. 30 seconds should do the trick....

 

By your description, it sounds like romps to me too. Does it sound like the video on start up? I switched to T6 5w-40 synthetic and it never happened again.

<iframe width="420" height="315" src="//www.youtube.com/embed/jtbgrgQXyGQ?rel=0" frameborder="0" allowfullscreen></iframe>

 

Yes, my truck sounds exactly like the truck in the video.

So, I guess it has the romps. (Sounds like something you could pick up in the PI.)

That sent me scurrying to the search function to find the cure for the romps and it doesn't appear to me, at least in the threads I found, that the hive mind has yet found a definitive cause/cure for the problem.

For many, switching to thinner oil stops the romps, but it doesn't for others, and consensus seems to be that it's only a band-aid fix for the root problem. Some are of the opinion that it's actually a software problem.

Or....I never found the right thread that announced the miracle cure.

I've run Delo 15-40 year round since the truck was new because it normally doesn't get that cold around here (sub 30 nights are rare in the winter) and I only occasionally get up in the mountains.

Tugly: I don't normally happen by Wenatchee, but if I do I might pester you.

 

I too was a loyal Delo user and did some very thorough searches on the 'romps' issue, all of them coming up relatively inconclusive. I was also unable to find whether or not it was harmful. There were days where it would romp at 65F. Once I switched to 5w-40, it's never happened again.

 

My truck had the romps a few years ago right when the seasons changed and the mornings were cold. I plugged in the block heater and that took care of the symptom but didn't cure the source of the problem. The romps later returned during the summer at very high altitude. Turns out that glow plugs are kind of important when baro is very low...

New glow plugs solved the problem. No romps since....not during the winter nor when at high altitude.