How much idling is too much at one time to hurt the mighty CTD? There are times when my family stays in the truck with the AC running and I run to the store to buy something. Is 10 minutes too long? Also, I have bought the grounding pin from Cummins to ground pin #22. Where exactly is this harness located (pictures would help)? Once I get it installed, how high should I idle the truck when running the AC? I would appreciate any info.

 

I think this is a good post that might help a little because I know nothing: Posted by stickbow on 07-04-07 titled "Help! Will idling for hours at a time damage my DTC"

https://www.dieseltruckresource.com/...t=long+idleing

Of course you may have already seen it judging by your pin purchase.

 

I recently had the rough idle PCM update and the report says excessive idleing. Personnaly I don't think I idle that much maybe hitching/unhitching the RV. What gives??????

 

Maybe traffic lights.

 

IIRC Cummins said that engine idle time is counted as any time the engine is running under 1000 RPM's and why many set the fast idle above 1,000 RPM's when setting for longer then 5 minutes.

 

I dont think it hurts anything to let them idle as long as you want. If your in the truck you can watch the temp. If it gets to high or low, then raise the rpm for a couple minutes. You want to make sure the truck is fully warmed up before you idle for very long though.

 

The consensus is to raise the idle, if you know you are going to idle for a period of time. i.e. Waiting for the wife to finish shopping, etc. Have the dealer enable the high idle, then you can control the idle.

For the auto trucks, it's a software switch that gets enables. For the manuals, there is either an ECM pin that gets grounded or buy the Cummins clutch switch/harness assy, then have the dealer enable the high idle.

I use the high idle, when cooling the exhaust down before shut-off, and when waiting for someone....1500rpm really makes for COLD AC.

I've heard that most downloaders will allow you to enable the high idle.

HTH

Tony

 

I've left mine running for days at a time when the temp drops below -30/35*C in the North country, if you turn it off at those temps chances are it isn't going to start again without a tiger tourch... I just set the High idle to 12-1500 and put the Trans in "N" with the parking break engaged. In the summer time I don't bother, I just use the TurboTimer when it's hot and shut her down...



..

 

DC and the dealers go by total mileage divided by the EMC's hour meter. So if you have 68,000 miles on the truck and the hour meter says 3,800 hours then you are averaging 17.89 mile per hour. The average is 35 MPH so that 17.89 MPH would trip the flag of too much idling.

You can see the EMC's hour meter reading by:
1. Make sure the mileage is showing instead of trip.
2. Turn key on, don't start.
3. Press and hold the trip button till the hours are displayed.

So even if you enable the high idle feature, the average MPH of the truck will still be low and flag the truck as having too much idle time.

 

I just make up for that by driving extra fast on the hiway

 

This is bad advice.


Cummins specifically recommends against extended idling, whether it's cold outside or hot outside.

There was actually a TSB issued for the 24V trucks that described how valve deposits from idling were building up and even causing bent pushrods (pushtubes in cummins lingo).

Idling is one of those things were the less you do it the better.

Now, if you've just been running the truck really hard, idling it for awhile isn't going to hurt.


Combustion temps and engine temps are not really correlated, so even when your water temp guage says the engine is warm, combustion temps can still be too low to prevent build-up.


Now, if you have an e-brake or some way to raise EGTs, I'd think you could idle almost indefinitely with no harm. As long as EGTs are 600 or higher, I'd say you're fine.

JMO

 

I don't have any reason to idle my truck excessively. That said, I don't think it hurts to idle them.

There have been numerous threads about this over the years. I still have YET to see a DOCUMENTED case of a Cummins engine failure due to idling.

If it was a problem, we would hear about them failing occasionally. WE don't.


It is just a machine and it doesn't care. Big rigs idle all the time. Our trucks up in the Far North have to idle all winter or they wouldn't be running at all. Idle on if you have the need, want, desire.

 

I have yet to see a Great White Shark personally, too. But I still know they exist.

Up North, there's no way to get around needing to idle. But saying it's needed versus saying it's OK versus saying it's GOOD are all very different things.

JH

 

In the trucking industry fleet managers constantly gripe and moan about the extra maintinence costs of idling and generally figure it to be double the cost of the fuel wasted. Also you can consider not getting the maximum useful life out of the engine before overhauling it a failure. Idling like big trucks for 10-12 hours a day will shorten the time for an overhaul by several hundred thousand miles. But unless they're hotshotting and living outta their Ram I doubt anyone here idles their P/U that much. Still though, 10 minutes here and 15 minutes there... If you've got this idea in your head that it won't hurt and it's ok.. well over time that's going to add up and it's not good for your engine no matter how you slice it.

 

To Hohn and Dieseljunky,

I am not saying that it is "good" for it. I am just saying I haven't seen any proof that it "hurts" it to idle.


Sure fleet managers are going to gripe about idling. It burns more fuel to idle than not. Fuel costs money.

I agree with you that it probably does shorten the life of the engine some. It is still putting wear on it to run. Of course, cranking it on a cold morning puts wear on it too....so how much wear the idling causes vs. the cold start...hmmm......honestly I don't know.


My point is a thread will pop up here every so often and create a debate like we are having here now. But in the end, nobody has provided a documented case of engine failure due to the idling that im aware of.

This board has almost 39,000 members. Some are very abusive to their trucks in many different ways. Excessive idling. Excessive horsepower. Pulling excessive loads in excessive cold or heat. I don't see any reporting any failures due to idling. You do read threads about blown head gaskets due to high pressure though...for example. You do read about transmission failures. You do read about lift pump failures.

Problems due to excessive idling?....SHOW ME.