mine idles at about 650-700 and I like it corse mine was a canada truck and its a 6 speed

 

It was actually my truck that Infidel was referring to. After the nozzles and DTT tranny went in and the weather heated up, it would often die when put into drive or reverse. I went to the dealership for the problem, they could find nothing. I had them check all voltages, asked specifically if it could have been a bad sensor and had them perform the high-idle reflash. They found no problems and the reflash did not help at all. I also took it to my local diesel mechanic, no solution. A friend told me to adjust the torx screw - and actually turn the idle up. Whether or not that "adjusts the idle", I don't know. Regardless, turning that torx screw made my truck quit dying and never set any code. Note that it did not need to be turned very much AT ALL to fix the problem.

Augusta

 

I changed my TPS sensor today & it has a sticker on it that says "Do not attempt to adjust the idle by turning the screws." So I take it from that you can turn the screw & raise or lower your idle or why would they tell you that? Common Sense, Right?

 

Can't you just reset the APPS after you turn the screw? Seems to me, you get a TPS code because it is seeing the wrong voltage at idle.....I think the APPS reset will set a new idle voltage after the screw has been turned. Anyone try the APPS reset after getting the code because you turned the screw?

 

yeah I rest the apps and the code went away but the idle speed is the same....850 is not bad...just seems like it would quiet down a bit if it were lower

 

Why exactly do you want slower idle? Wont it give you less oil pressure, less heat and a higher possibility of valves sticking etc? Just seems like a lot of work for nothing....but problems.

 

I thought most people were interested in raising their idle so less build up occurs.

 

850 RPM (or whatever) is hard-coded into the ECM. It's going to add fuel until it reaches 850 RPM. The APPS doesn't kick in the control logic until you press the long, skinny pedal far enough to tell the ECM that you're "off idle".

Rusty

 

Seems that all this is much ado about nothing. Why is idle noise such a big concern? You aren't idling your truck for long periods are you? Cummins says no-no.

There is nothing to gain from a lower idle that would make it worth considering. If you want to RAISE your idle at times, check a high idler like one from Practical Solutions.

www.psdieselproducts.com

 

When Cummins South in Savannah,GA (Pooler is the town actually) put in my rv275's thay adjusted my idle down by using a computer there hooked into the ehgine data plug. They lowered it to 750rmp's and it's still there today. Have not had any issues when putting the auto in gear. Lond story short, some Cummins dealers have the equipment to do so and some don't. Just my experience.

 

hey man I adjusted my idle screw and now my trucks throwing a tps code I was wondering what you done to fix it

 

You adjusted the idle screw to higher than idle. The idle validation switch does not come on anymore- re-adjust the screw to where it was before.

The 24V idle speed is in the software of the ECM, and the emergency idle speed in the software of the VP44. The "low idle stop" on the 24V can not raise or lower your idle speed.

 

so all I need to do is read the voltage coming out of the sensor and adjust back to stock

 

Or read this Instruction by Timbo and go from there.

 

Hope this helps, from Mopar1973man's site, from the man himself.Popped too low in pressure if your rising above 800 RPM at all. All Cummins ISB engine idle at 800 RPM. The only way to increase idle speed is to drop the pop pressure below 290 bar. Then to show the specs even Dodge FSM specs say 293 bar is bottom. Eample my OEM stock injectors tested out at 260 bar at 120k miles. The idle was 850 RPM.

[img]blob:https://www.dieseltruckresource.com/c3c5b973-921a-4668-a418-199d8957c0b2[/img]

Span plus or minus... PSI to Bar

4500 - 250 = 4250 4500 PSI = 310 Bar stock

4500 + 250 = 4750 4250 PSI = 293 Bar

4750 PSI = 327 Bar

Proper injectors should hover with +/- 10 RPM from 800 RPM. The engine load should be like 7% to 10%.

Show you reversal. I'm 7 x 0.010 injectors (+150 HP) and popped at 320 bar. Cleaner, no smoke, slightly less flow but idles exactly 800 RPM +/- 5 RPM. Engine load when new was 13 to 14% this shows the VP44 working a bit harder to get pop pressure. Now with nearly 100k miles on the injectors I'm down to 6 to 7% engine load but rock solid at 800 RPM idle.

NOTE: There is member here that had injectors loose, over -10 bar after running about 20k to 40k miles. If you popped too low near the lower margin then it will be a very short life of the injectors. Like shops popping for 300 bar only last like barely 50k to 75k miles and already popping too low.