LBZ Idle

[BriteWhiteRam]

Hi I was just curious if there was a way to set up one of my DSP5 tunes to allow me to raise the idle for cold weather, or is there only the base idle? It would be nice to be able to have a higher idle on one of my tunes, then I could select it whenever I needed it

Any insight? Thanks

[andrewjamesbond1]

As of my knowledge, you don't have an Idle table in each DSP, therefore, you can only control the idle of the whole truck, not each individual tune. Are you wanting to have a higher idle during colder weather for helping warm up the engine, or do you want a higher idle all the time? If option 1, increase your idle speed in the lower ECT temperatures in your base idle speed. If option 2, you might just have to flash in a higher idle speed when the truck is warm during cold seasons. So far that would be the only way I could figure it out...

[Bearce Sr]

From my understanding use 1 of ur spots on switch using stock tune bang idle 2 1000rpm when ready 2 roll move switch 2 diff spot. I don't have dsp5 yet but that's what i would do c ya

[DURAtotheMAX]

From my understanding use 1 of ur spots on switch using stock tune bang idle 2 1000rpm when ready 2 roll move switch 2 diff spot. I don't have dsp5 yet but that's what i would do c ya

spoken like a true armchair ASSuming tuning expert. Why would you try to help him out and offer advice when you dont even have DSP5, or any knowledge about it?????? I dont understand that about forums. If someone doesnt know the answer to something, and they ask a question, do you think they would want an "answer" from someone who ALSO doesnt know the answer to the question????? :music_whistling_1:

Thats like me barging in on a meeting of nuclear physicists and saying "oh hey guys, have you tried making the reactor work this way? I think that would work great!"

and no, this theory/idea of yours has zero possibility of working, for the reason that andrewjamesbond said DIRECTLY above your post. Each DSP tune does not have its own idle table.

The only way of doing it would be to use the main base-idle table vs. ECT, setting the idle speed high below, say 40* ECT. But then again, I dont know how that would affect the park/drive idle offset....if the engine would still try to use the base-idle tables even when in drive. In which case the aformentioned trick would not work, because then as soon as you put it in drive, the truck would try to push through the brakes.

[BriteWhiteRam]

What Im trying to accomplish seems like it cannot be done with the current DSP5 configuration, I dont want to turn up the base idle of the whole truck, because as DURAtotheMAX states the idle increases for the whole truck, and its not good for the transmission, I tried to fiddle with the idle before and didn't like the result a whole lot

I was thinking that I could use one of the DSP positions as a manually controllable High Idle of sorts, for when its -35C and I want the RPMs to go up to 1200-1400rpm instead of 1000rpm, thats one thing I miss about my Cummins is the ability to manually increase the idle using the cruise control function, when in park you hit the cruise button the rpm would kick up to 800 and by pressing the accel/decel buttons you could increase the idle to up to 1400rpm if you wanted

The LBZ-LMM only have an automatic High idle which is OK, but not to my liking, and I'm unsure of any mods that can allow it like you are able to do on the LB7

[killerbee]

On the LBZ, you can set up a high idle/PTO switch, and use the cruise control buttons.

[andrewjamesbond1]

^^^ Thought that was only with the LB7... hmmmm... :) how do you go about doing this? Is it any different than the LB7's?

[JoshH]

spoken like a true armchair ASSuming tuning expert. Why would you try to help him out and offer advice when you dont even have DSP5, or any knowledge about it?????? I dont understand that about forums. If someone doesnt know the answer to something, and they ask a question, do you think they would want an "answer" from someone who ALSO doesnt know the answer to the question????? :music_whistling_1:

Thats like me barging in on a meeting of nuclear physicists and saying "oh hey guys, have you tried making the reactor work this way? I think that would work great!"

and no, this theory/idea of yours has zero possibility of working, for the reason that andrewjamesbond said DIRECTLY above your post. Each DSP tune does not have its own idle table.

The only way of doing it would be to use the main base-idle table vs. ECT, setting the idle speed high below, say 40* ECT. But then again, I dont know how that would affect the park/drive idle offset....if the engine would still try to use the base-idle tables even when in drive. In which case the aformentioned trick would not work, because then as soon as you put it in drive, the truck would try to push through the brakes.I disagree. It would be pretty simple to make a tune in the DSP idle higher than another tune. It wouldn't be very good if you tried to drive it in that tune though. It would be like doing a mild boosted launch all the time. If you really want to do it, you can do it by modifying the torque based fuel table for whichever tune you want to be your "high idle" tune.

[andrewjamesbond1]

I disagree. It would be pretty simple to make a tune in the DSP idle higher than another tune. It wouldn't be very good if you tried to drive it in that tune though. It would be like doing a mild boosted launch all the time. If you really want to do it, you can do it by modifying the torque based fuel table for whichever tune you want to be your "high idle" tune.

^^^This is why I love tuning! I never would have thought of that. This won't make it lope, will it?

[JoshH]

What little I've played with it, it hasn't. You just have to pick a fuel quantity (probably somewhere around 25 mm3) and extend it all the way down to the 0 ft-lbs row out to whatever RPM you want it to idle at.

[killerbee]

I disagree. It would be pretty simple to make a tune in the DSP idle higher than another tune. It wouldn't be very good if you tried to drive it in that tune though. It would be like doing a mild boosted launch all the time. If you really want to do it, you can do it by modifying the torque based fuel table for whichever tune you want to be your "high idle" tune.

Not. Idle control is an rpm/fuel feedback loop.

Also, be careful about changing any bosch 0 TPS row. Our test vehicle stalled unpredictably.

[JoshH]

Not. Idle control is an rpm/fuel feedback loop.

Also, be careful about changing any bosch 0 TPS row. Our test vehicle stalled unpredictably.What are you talking about? I never said anything about changing a 0 TPS row. What I posted works. I've done it before.

[BriteWhiteRam]

What are you talking about? I never said anything about changing a 0 TPS row. What I posted works. I've done it before.

Could you please be more specific about how to go about doing this? do I change all the vertical rows from 37-812ft/lbs from 300-1200rpm to 25mm3?

how will changing the fuel to 25mm3 increase the idle?:nixweiss:

[andrewjamesbond1]

From what I have scanned, the truck commands between 10-15 mm3 of fuel during idle. By changing the fuel to 25 mm3, it will "idle" higher.
As to what to exactly change, I am not sure, would have to play with it, or have Josh post a screen shot (...wink wink :D...)

[cumminsDK]

Josh, you have the right idea. What I have found to work is to set all cells in the zero pedal position row in "pedal position to desired torque" to 185 from the left side up to desired rpm then in "torque based fuel" the upper left corner must be filled in down to 185 and over to desired rpm with about 27 for it to work in colder temperatures. If it works when warm but not when cold raise the torque number our the fuel quantity. Remember in the lmm to do all pedal position to desired torque tables. Maybe bballer can chime in if I'm making this more difficult than it needs to be, this scenario works for me but I call him the lbz guru as he has an excellent understanding of how this ecm uses the data we input

[cumminsDK]

Also I have had NO stalling issues and have done this on dozens of trucks

[BriteWhiteRam]

Also I have had NO stalling issues and have done this on dozens of trucks

So the truck will idle at 1200rpm(what I have turned it up to) constantly until i turn the switch to another tune?

Are there other parameters I should consider to help with warmup such as vane position? maybe to help eliminate the whistle?

[cumminsDK]

I set the vanes to all the way closed to help put a load on the engine so that it will warm up faster this will also make it whistle more however the increased idle speed is enough for it to warm up

[andrewjamesbond1]

Can't wait to try this on mine, have to wait until Thanksgiving when I finally get my LBZ! Wouldn't mind a warm up tune. What RPM is safe to high idle on? With a remote start, is it bad to have it high idle right away to say 1200 rpm?

[BriteWhiteRam]

Can't wait to try this on mine, have to wait until Thanksgiving when I finally get my LBZ! Wouldn't mind a warm up tune. What RPM is safe to high idle on? With a remote start, is it bad to have it high idle right away to say 1200 rpm?

Thats a good question, I'm interested on this as well, I thought about setting it to 1400 but im worried it may be too high.... especially with remote start

[andrewjamesbond1]

Yeah, maybe 1000-1200 with the vanes around 95% to work the truck might be the sweet spot. Personally, on the trucks I have played with, I have set up the ECT vane adder to close the vanes when cold, and then back off when finally warm. Helps warm the truck up plus the owners like the vanes open at idle to get more of an lb7 sound.
BriteWhiteRam - did you purchase a remote start for the lbz? If so what brand? Looking to get one for christmas hopefully :D

[cumminsDK]

If you find the right spot it will slowly speed up when cold but jump right to 1200 when warm.less fuel and it wont idle up when cold more it jumps right up.i don't recommend immediate high idle but a few seconds of oil pressure and all cylinders firing normally

[BriteWhiteRam]

Yeah, maybe 1000-1200 with the vanes around 95% to work the truck might be the sweet spot. Personally, on the trucks I have played with, I have set up the ECT vane adder to close the vanes when cold, and then back off when finally warm. Helps warm the truck up plus the owners like the vanes open at idle to get more of an lb7 sound.
BriteWhiteRam - did you purchase a remote start for the lbz? If so what brand? Looking to get one for christmas hopefully :D

Its an astrostart 2-way, I wish I had waited, you can now get command start that works with your smart phone, I wish I had that now, the 2-way doesn't work unless you're 400' from the truck, which sucks because Im usually over a mile from my truck when Im at work, It would be nice to start it before I got there for about 5mins or so

[killerbee]

Josh, I see no way to regulate zero throttle (idle) rpm between dsp positions. If you have, please feel free to share.

[JoshH]

Josh, I see no way to regulate zero throttle (idle) rpm between dsp positions. If you have, please feel free to share.I have never done it with a DSP switch, but I have raised idle RPM with the torque based fuel table (B1102) just as I described earlier. I was just playing around a little when I discovered it. Didn't really do much with it, but I see no reason why it wouldn't work with a DSP tune to control idle speed. I would try it, but I don't have a DSP switch in my truck. If someone with a DSP switch wants to test it, I'd be happy to make the changes.

[andrewjamesbond1]

I can tell you by thanksgiving! (... hopefully)

[andrewjamesbond1]

Josh, is there a way you could send me a screenshot of what exactly you did with the Torque Based Fuel? I understand you need to call for more fuel, but unsure of how you set it up exactly.

[killerbee]

You can raise rpm this way. But without predictable results. For example, as soon as you turn on the AC, put the truck in gear, or turn on lights for that matter, rpm will change. Even a different oil weight will change it. That is because this isn't an rpm control technique, but rather fuel control.

As I stated before (for the benefit of anyone who wants to experiment), be aware that changing the LBZ 0 TPS column to non-zero torque or fuel numbers can result in very anomolous fuel pressure loss, and stalling. Losing your power steering at the wrong time can really hurt. Your mileage may vary, but I nearly wet my pants. :)

[JoshH]

Josh, is there a way you could send me a screenshot of what exactly you did with the Torque Based Fuel? I understand you need to call for more fuel, but unsure of how you set it up exactly.I'll post a screenshot later this evening. I don't have anything on the computer I'm using right now, but basically what you are doing is raising the fuel quantity at lower torque levels. What happens is the ECM automatically lowers the requested torque level to maintain idle speed. It will lower it all the way down to 0 in an effort to achieve desired idle speed. What you must do is enter a fuel quantity that will be high enough to raise idle speed to your desired level, and extend it out to that RPM in that table. So if you want the truck to idle at 1200 RPM, you would select a fuel quantity (we'll say 25 mm3 will get you where you want). Now you find the row that is at least that much or more. Highlight everything from the upper left corner of the table over to the 1200 RPM column and then down to the row just above the row you previously identified. Now enter 25 into the highlighted region. If the truck doesn't idle at your desired RPM, but your fuel quantity at idle is the value you entered, you will need to raise the fuel quantity a little.

[JoshH]

You can raise rpm this way. But without predictable results. For example, as soon as you turn on the AC, put the truck in gear, or turn on lights for that matter, rpm will change. Even a different oil weight will change it. That is because this isn't an rpm control technique, but rather fuel control.

As I stated before (for the benefit of anyone who wants to experiment), be aware that changing the LBZ 0 TPS column to non-zero torque or fuel numbers can result in very anomolous fuel pressure loss, and stalling. Losing your power steering at the wrong time can really hurt. Your mileage may vary, but I nearly wet my pants. :)I agree with you, to a point. If you set the fuel quantity to a point high enough that it can actually start falling back off of the "desired" quantity, it will maintain pretty well with small loads such as the A/C compressor, but I do not recommend using this technique for in gear operation (as I stated earlier). I feel you are purposefully trying to poke holes in this operation for whatever reason, but I promise you that you can get pretty damn close to whatever idle speed you want. I know it isn't an ideal solution, but sometimes you have to work with what's available.

Also, like I stated earlier, nowhere in any of my posts am I recommending anyone to change anything in any of the throttle position tables. Also, just to reiterate, I do NOT recommend driving with a tune you have modified this way. It could be very dangerous and make it difficult for you to stop.

[andrewjamesbond1]

12286

Something like this?

[JoshH]

Change the 185 row too, but yes, that should do it.

[andrewjamesbond1]

Gotcha. I will try that when I get my dmax and dsp switch :)

[BriteWhiteRam]

Michael you mentioned a different way of doing it using the cruise, could you expand on this?

[JoshH]

He's talking about the PTO controls.

[BriteWhiteRam]

Okay but how does one go about setting it up?

[Ryan_Dmax]

Ok so I changed my torque based fuel to 27mm3 down to 190ft lbs and out to 1200rpm and it didnt work. I also tried changing TPS to 185 but that just made the truck shutter but didnt stall. Any other tables I need to change or do I need to increase fuel?

[JoshH]

Ok so I changed my torque based fuel to 27mm3 down to 190ft lbs and out to 1200rpm and it didnt work. I also tried changing TPS to 185 but that just made the truck shutter but didnt stall. Any other tables I need to change or do I need to increase fuel?Can you post your tune with the changes you made?

[Ryan_Dmax]

Can you post your tune with the changes you made?

Il pm you the tune

[Ryan_Dmax]

12393
12394

Nvm I figured out how to screen shot

[JoshH]

Did you also change the medium and low altitude torque based fuel tables?

[Ryan_Dmax]

yes all 3 have been changed