PCM Flash to Grand-AM Cup PCM

[Rusty]

I performed a full flash with a stock operating system. I added my VIN number and then read the PCM. I changed the VE table and flashed cal changes. EFI required me to purchase another license which I did. That is another conversation.

This is where I am now. We replaced the cracked FAST intake due to GM valley cover bolts pushing on bottom of the aftermarket FAST intake. After correcting intake, car is idling correct and seems to be running better but needs a lot of adjusting to open loop.

After 15 seconds after start, I get flashing check engine light. Only P1689 and P1541 codes that are for traction control. I imagine that it is flashing MIL due to values from O2 sensors 1 bank 1 and 2. O2 sensors 2 bank 1 and 2 are removed.

Engine Information:
Largely ported and polished heads (243),
Cam has lift and dur. greater than 2006 Z06 specs.
hooks headers
Z06 injectors
383 CI
3" exhaust, no cats, no mufflers

I am attaching my tune file and logged data. I appreciate any advise on changing settings to correct.
Thanks!

[Rusty]

Post pics of your PCM.

I have attached a couple of pictures of PCM. Do you think I should go back to older OS?

[joecar]

Rusty,

Is that a PCM that the Grand Am rules require you to race with...?

Is that the purpose of your vehicle, GA racing...?

The flashing MIL indicates misfires, unless the GA PCM gives it special meaning.

If the rotating assembly (from pulley to flywheel) and/or the crank sensor, then a CASE (crank angle sensed error) relearn may be needed, as this steers the misfire algorithm.

[joecar]

Your log shows LTFT's pegging at 25% at idle... your NBO2's may not be working right which would throw some DTC's which would light the MIL steady (but misfire overrides and flashes the MIL).

Hmmm.... that PCM is set for 31* advance regardless of the spark tables and spark modifier tables...? Am I interpreting correctly...?

[Rusty]

joecar,
Thanks for the help on the flashing MIL without codes. We have lower than expected exhaust temps from cylinder 8. We will resolve those issues today. Assuming the mechanical and crank sensor are resolved. And assume that I relearn the CASE after removing the misfires.
What do you suggest to get open loop running closer to stioch?
What PIDs should I add to the log list help?
Should we get a wide band O2 to work with EFI? If so, please recommend one. I see the list which works with EFI but not sure which is best for us. Need no more technical problems and it to connect easily to EFI live and FAST systems. Also, if it can be a hand held sensor, it would help with other open loop cars.

[Rusty]

Rusty,

Is that a PCM that the Grand Am rules require you to race with...?

Is that the purpose of your vehicle, GA racing...?

The flashing MIL indicates misfires, unless the GA PCM gives it special meaning.

If the rotating assembly (from pulley to flywheel) and/or the crank sensor, then a CASE (crank angle sensed error) relearn may be needed, as this steers the misfire algorithm.

I can change the PCM with other systems per our rules. We have remained with this GM PCM because it was working great with the last engine couple of engines. All other people involved are wanting to switch over the a FAST and removing the complexity of the GM PCM.

[joecar]

Yes, fix the physical misfires first before attempting a CASE relearn.

To get open loop running closer to stoich you could do one of:
- raise either of VE B0101 and/or CFOL B3605 a little (trial and error);
- do AutoVE using a wideband, this will then let you specify the AFR you want to see (can you see the time-saving advantage of this);

By doing the second option, then the AFRs specified in B3605|B3618 will show up on the wideband (when PE is enabled, the richer of B3605|B3618).

Do you have FlashScan V2...? If so then a wideband like the LC-1 is cheap and simple, it connects serially to V2 using a RJ-12 to stereo 2.5mm cable as sold by forum member TAQuickness; see this: showthread.php?t=8115

By placing a connector on the end of the LC-1 you can make it portable.

For racing, you could probably run with an OLSD tune... avoiding the MAF and NBO2 has several advantages including improved transient response time (in my $0.01 opinion). How much proportion of the time do you spend at WOT vs Part Throttle...?

To have even more control over OL AFR, you could run COS5 (altho this requires a little more work copying all the tables over... and you have to first see if OS 12212156 is compatible with your PCM... if your PCM is a "0411" PCM then it will run.

I suppose you should consider/experiement with these during off-season.

Hmmm... you should also carry a spare PCM tuned with your latest good tune.

How did they disable/fix timing advance to 31*...?

[joecar]

Include these pids:
VSS
RPM
TP
MAF
MAP
IAT
ECT
AFR
SPARKADV
KR
IBPW1
IBPW2
DYNAIR
DYNCYLAIR_DMA
LONGFT1
LONGFT2

Maybe include these:
HO2S11 (not HO2S12 or HO2S22)
HO2S21 (not HO2S12 or HO2S22)

For AutoVE or AutoMAF, keep the channel count to 24 or less (giving 10 updates/second); see bottom of PIDs tab in scantool.

[Rusty]

I will adjust the PIDs as you listed. I use flashscan v1.2. Do you have an opinion of a wide band that will work with my hardware / software? I see that FAST sells a stand alone that logs data but I do not know if compatible with EFI Live. Also it is costly ($400+). I would rather pay for quality and a device that is somewhat easy to use and common.
I appreciate your advise on the tuning. BTW: cylinder 8 had intake value open due to stock valve cover and rocker arm clearance. I think we got that fixed. Ready to tune!

[joecar]

Any basic wideband (LC-1, PLX, etc...) will do... you don't really need to have a gauge, you just feed the wideband analog AFR signal into FlashScan V1... the requirement is that it outputs a 0V-5V linear analog signal representing AFR (e.g. LC-1 outputs a linear 0V=7.35AFR, 5V=22.35AFR).

If you use one of the "supported" widebands, you can simply use the pre-made calc pids (for AFR and BEN) for that wideband... or we can make custom calc pids... (I reprogrammed my LC-1 to give better resolution (e.g. 0V=11AFR, 5V=16AFR) so I made my own calc pids (see attached... oh, I log EQIVRATIO instead of AFR, where EQ = stoich/AFR... I taught myself to think in terms of EQ rather than AFR).