PDA

View Full Version : Smoothing out idle



Chadsix
March 30th, 2012, 01:29 AM
I was wondering how i would go about smoothing out my idle. I got a pretty hefty fueling tune and have a little longer crank and a lopeyish idle and wasnt sure what table i can adjust to get a better start amd smooth idle. I would like to make the idle smoother with my lesser tunes also. I k ow i have a ton of stupid newby questions im just trying to learn thank you

DoghouseDiesel
March 30th, 2012, 01:38 AM
Look at your duration table and see where its idling at.

More than likely you have too much of a gap between values and one is probably too low and the other is likely too high.

That will give you the loping condition.

Chadsix
March 30th, 2012, 02:21 AM
This will be in the top left area of the table correct? Should i bring down the duration or should i add to it? Thank you very much for the input

FUBAR
March 30th, 2012, 02:54 AM
Create less of a transition as Rich was saying. For example, 12mm3 to 15mm3 you wouldn't want 300uS the 500uS, more like 300uS then 350uS. (numbers used purely for example)

Chadsix
March 30th, 2012, 04:29 AM
I will take a look tonight when i het home. Im just confused on what area of the table i need to focus on. This is what has confused me since day one is some of the tables.... A picture of what i need to focus on would help ha ha jp... Less you want to... Thank you guys for all your help. I apologize for being dumb with all this. Ive flashed and changed my ecm like 100 times now im just waiting for it to go dead

DoghouseDiesel
March 30th, 2012, 04:57 AM
What you need to do is this.....

In the V7.5 Tune Tool, go to Edit and then down to Properties and you'll get a pop-up box that looks like this.

12829

Make sure the boxes under the PID Data Links are selected.

Then, go to the tab that says 3D Surfaces.

12830

Check the box that says High Contrast Font Colors.

From here, hit okay and hook everything up to the truck.

Open the V7.5 Tune Tool and open up the Main Injection Pulse.

12831

Now, keeping the V7.5 Tune Tool open, Open up the V7.5 Scan Tool, turn the key to run, connect as to the truck as normal, making sure the PID's you're logging are showing the Main Injection Pulse, start the truck and begin logging. Also, make sure the tune you open in the Tune Tool is the same one you have loaded on the truck.

Let it idle and what you'll see is something like this (this isn't the Main Injection Pulse, it's just a picture I had handy).....

12832

This will highlight EXACTLY the cells being utilized and shows you the areas you'll need to correct to bring the idle in check.

DoghouseDiesel
March 30th, 2012, 05:31 AM
Here is the Main Injection Pulse table highlighted.

This looks like it was either cold, or I had the truck in gear, as it's normally in the 8 - 12mm3 range when the truck is warmed up and idle in park or neutral.

12833

Chadsix
March 30th, 2012, 11:58 AM
You could have givin me some better info but guess this will do.....joke! This is great thank you very much if i turn down the fueling duration the idle is better but my low end suffers im just gonna find a happy medium. Maybe play with my limiters down lower in the rpm range and have ot start fueling before it sees boost ill see what the smoke output becomes Truck runs amazing and is smooth as silk other than that. Ill play around amd post back if i get upside down. Thanks guys

FUBAR
March 30th, 2012, 01:18 PM
It's not so much as cutting the fuel back, but creating less fluctuation. I cheated and have scaled my first mm3 axis 10mm3 then 15mm3, etc so it don't sit there and bounce up and down...I also smoothed out the transition as well though.

DoghouseDiesel
March 30th, 2012, 01:18 PM
I'll try and make it easy next time....

:hihi:

DoghouseDiesel
March 30th, 2012, 01:32 PM
The changes you make at idle shouldn't be affecting anything else as any time you're on the throttle, the rail pressure is going to be higher than the ~7200 that it idles at. So if it's effecting your low end, you're adjusting too much of an area. Idle is only 3 - 4 cells MAX.

Chadsix
March 31st, 2012, 07:41 AM
Ive messes with some things and i think i can live for now.... Just in general if i wanted to get the truck to idle smooth as silk what would i adjust. Its ideling normal just the normal quivers and shakes you get even on stock progeamming. Didnt k ow if there was something that could be adjusted to make it still and even.