VE tune -> C6001 -> p0101, p0102, p0103 settings

[maudyZ28]

hi all,

after a comment made by Joecar in the 'wot afr' thread and a few PMs we decided a test was inorder.

I have previously set up my VE table in my standard OS for a 99 auto camaro.
I had P0101,0102,0103 set to NOT REPORTED in C6001

The VE was obviously calibrated and all was fine. (not at idle -> cheated and used STFT to find nice spark as needed car everyday back then)


NOW i switched to COS 3

I did a quick run and noticed my VE table was still slightly out, more at idle as this wasnt as good hence why I was trying to get it redone today.
This is still with the C6001 codes as NOT REPORTED.


Joecar had mentioned that these need to be set to 1-TRIP for the PCM to exclusively use the VE table over the MAF. I dont have my MAF any longer so assumed it would use VE only (even with codes set to NOT REPORTED). Joecar mentioned that the PCM will still not exclusively use the VE table, it will used some 'internal' parameters and mix it with the VE table to calculate airmass values.

The BEN values are as below



I think this VE table (which was dialed in perfectly, except at idle) is different as the 'internal' parameters of the COS 3 OS maybe different.


To test the 1-TRIP theory, I changed the codes in C6001 to 1-TRIP for p0101,p0102,p0103, and made sure the scanner reported a trip. (in this case it tripped P0102). I then procedded to do another log and check the BEN values.

THEY HAVE CHANGED BUT VE IS THE SAME !!!!



( i know the MAPs are small but each cell has over 20 counts, again not a lot but the car cannot be used on the road at present so this is all I could manage around my street )


So as Joecar originally said they DO need to be set to 1-TRIP such that the VE is EXCLUSIVELY used. I shall be doing this from now on. Hopefully thsi will help some of you guys out who accidently set P0101, P0102 and P0103 to NOT REPORTED in C6001. (the auto VE tutorial DOES NOT tell you to do this, but I still assumed you needed to, dont make the same mistake!!!)

[Sid447]

Hello Maudy,

I've never tried this any other way; I've been SD since 2004 and C6001 has always been set the same as you'd find in the 2000 to 2004 HSV GTS factory tunes, i.e. P0101, 2 & 3 set to "Non Emissions".

[joecar]

Non-Emissions may be ok as long as a DTC triggers.

I found some calibrations where Non-Emissions did not trigger the DTC, so in this case 1-Trip is used.

I always check for a MAF DTC as confirmation that the VE is now exclusively in use.

The AutoVE tutorial should probable be edited to include a phrase saying to check for the presence of a MAF DTC.

[andysc3]

Yep, I updated my tune where p0103 would trip. Loaded it, started my truck. And the afr was around 12.9-13.5 at idle. Did two 30 min logs and its running much better. Now I just need to log some wot runs to the the pe where it needs to be.

[swingtan]

I think the big change is between the initial value used and "any other" value used.

Initially, the setting in {C6001} was set to "Not Reported", so the PCM would never see that the MAF had failed. I can only assume that the MAF was left in place and was still working as I'd have thought that the engine would not run if the PCM could not recognise the MAF had failed and the MAF signal was missing. I know that in the E38, if you set the values this way and remove the MAF, the engine will fire and then die, as there is no active air metering involved. IE. The MAF is misssing and the ECM will not use the VE table as it doesn't know the MAF has failed. If the MAF was removed and the car still ran, I can only assume that in the LS1 and COS-3 in particular, more blending / sanity checking is done between the MAF signal and the VE table.

As joecar says, you must get the DTC for the failed MAF to ensure that the VE table is being used. A quick DTC check is all that is needed after the first run with the SD tune.

Simon.