boosted camaro tuning in SD mode

[snax]

I have followed the tutorials to put this 2010 camaro into SD mode following swingtains tutorials. If you look at the log I have posted you will see at 3360RPM the APCYL_DMA pid goes from .81 down to .47 and back up again. Ignition timing is following this PID and timing is going from ~8degs to ~14degs, air fuel also starts to go lean all the way up to 15.7:1 at 115kpa of boost. From what I understand APCYL_DMA is calculated airflow and is used for various maps such as ignition timing so I understand why the timing is going nuts but why is the calculated airflow going nuts.

Can anyone see anything in the log or tune file that would cause this? this is my first boosted E38 ecu to tune and its not being very friendly.

11815
11816

[swingtan]

Is there anything you are forgetting to tell us? Like is the engine misfiring, breaking down at this point? Any DTC's being thrown? Is the MAF removed, or just disabled?

My first guess would be an ignition issue causing the spark to fail, you would hear this as a series of fast sharp backfires in the exhaust.
Next would be the MAF re-enabling at this point and causing an upset to the measured airflow.

Just two initial thoughts.

Simon

[snax]

Yes, on the dyno the car would break up and misfire at that point but I had assumed it was because of what was going on with the timing and calculated airflow. I had not considered an ignition problem. Am I correct in my understanding of the APCYL_DMA pid being calculated airflow based on the VVE table? How can i check to see if the MAF is re-enabling? I thought I had the MAF disabled in the tune but I did not remove the yellow wire from the harness.

[etmotorsports]

If the APCYL_DMA pid is doing that i would say the ecm is calculating it for some reason remove that yellow wire on the maf see if that fixes it and if you are making for the 120 KPA boost use the zr1 sensor it isn't expensive from a gm dealer.

[etmotorsports]

Its a hassle for your 1st e38 in speed density but once you get done the car will drive so much better.

[snax]

I ran a search for the map sensor a while ago and i thought it was a 2.5bar that came stock on the 2010 camaros? The car runs and drives awesome, im thrilled about that...its just the boost tuning that is giving me fits.

[swingtan]

I'd pull the yellow wire for a start. I'm thinking the MAF happens to reach the limits in the current tune settings and re-enables it's self. the ECM will then rely heavily on the MAF signal which is probably a bit off and causing these issues. If in doubt, log "MAFFREQ2" and see what it does as you go through 3600 RPM. I'm guessing the frequency will hit 14500hz......

[etmotorsports]

the stock camaro is a 1.5 bar i believe the zr1 is a 2.5 bar but if you don't have over 7psi your good with the stock one

[scdyne]

What is the part number for the MAP you have in the car right now? If it's the infamous "2.5" bar GM MAP sensor (12580698) used previously in the Cobalt, ION, etc. then
These should be:
B2101 = 207.6563
B2103 = 9.00

[etmotorsports]

i don't know the part number i will be working on the car tomorrow and ill check