6.0 first time tuning

Hello ll,
I am new to tuning and put a 6.0L in my 1995 pickup. I was going to put a procharger on it and still might but for now I am tuning without. I believe I am getting close but would like more opinions. I cannot get it to keep from going rich when I let off the throttle. I have left it go rich otherwise when I come off idle I get a bad hesitation. I currently am using a 2bar speed density operating system 411 PCM. NV4500 manual transmission. This is a new long block that is bored .040 over. Ls6 intake and a melling mtc8 cam. I have installed 65lb DeatschWerks injectors 16u-00-0065-8. I have a few questions below.

1) Would I be better off going back to the MAF operating system.
2) Is there a way to keep it from going rich when I let off.
3) Am I going in the right direction and just need to keep going.

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Any help would be appreciated and thanks in advance. I live in Moline ILL if anybody is close and does this on the side.

Remove the 1 bar MAP channel if you are running a 2 bar sensor. You only want to use one map channel to not skew data.

You need a wideband o2 sensor in your logs so you can properly dial in the airflow model. The VE needs to be done separate from the MAF and vise versa where the MAF needs to the the VE "disabled".

If you've been trying to calibrate the VE with the MAF still working, it makes sense as to why your VE table looks so bad.

The MAF can still be used in this operating system, no need to revert back to anything right now. If you are going to use boost in the future you can just remove the MAF and do speed density only.

I do have dual wide bands on the truck but I do not have a Pro version. I was wanting to get one but do not have it yet. I did have a tune file to fail the MAF and PE. I made two more runs with the MAF failed and attached them. Is there a way when taking the data you can get it to filter out the data below 2 percent throttle.

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Thanks again,

As a backup, always set the MAF fail high to 0hz. Showing code P0103 in the DTC's is the sure fire way to know it's in speed density.

The PRO feature set is not required to log the wideband. For probably 10 years now people have been wiring the wideband into a 5v circuit in the computer that isn't being used. For example, this computer can use the EGR circuit. Enable it in the tune, wire the 5v wire from the wideband into the EGR circuit in the computer and create a custom channel to log the commanded AFR against the actual AFR so you can dial in the VE table and MAF curve. Just use one of your widebands.

There are several youtube video's and write ups you can follow to do this. When you do it this way, you never have to disabled PE (you shouldn't ever do that anyway).

Sounds good and it looks like Blue connector pin 55 is the EGR position feedback. I will get this hooked up and try that.

Thanks again for the help,

Likely the reason you are staying rich is the rapid throttle transition and size of your injectors. You're hitting the minimum pulse of the 65lb injectors and still getting to much fuel. Try this out and see if it helps. Go to Fuel tab in your tune then click transient and reduce the min fuel milligrams by .005 and see if you go leaner with the throttle closed on your coast down. Adjust by .005 until you get the result you are after.

Ok so I had to enable the EGR and connected the wire from the wide band to blue connector pin 55. This all seems to be working good now and i can read the wide band. I also adjusted the min fuel milligrams from .045 to .015 and it has helped the rich condition when I let off the throttle. Thanks to both for the help on that.
When I am data logging this with the wide band should I force open loop?

Yes, disabled all fuel trims and closed loop functions as well as reset the fuel trim data with the VCM scanner. Make sure the EQ ratio open loop table is set to 1.00 for temps above 140-150 degrees where you will be gathering data.

Create a graph that will log the commanded AFR against the actual AFR so you can put that data directly into the VE table or MAF curve. Which ever one you wish to calibrate first. Remove the MAF channels and disabled the MAF if tuning the VE and set the tune to MAF only with the dynamic airflow high rpm disable setting if tuning the MAF.

The VCM scanner section should have a few write ups in the sticky pages for helping you set it up, or there are probably youtube video's out there on that as well.

Also make sure you 0 out the egr airflow table while it's enabled. I've found this will add in airflow and skew your tuning.

This is working great. I attached the last one that I logged. In this one i went a little higher on the RPM range than I had been. Let me know if you see anything that doesn't look right.

Thanks again for the help this has been incredible as I have been struggling.



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