Auto VE trouble (yes another one)

[SCP Perf]

I am working on my first tune using EFIlive and have been trying to read as much as possible. Fortunately/unfortunately there is alot (actually an overwhelming amount) of information on this forum, and I am not sure what I am doing wrong.

I have access to a load bearing dyno that I have been using to do the auto VE process.

Car being tuned: 2001 Camaro
LSX block bored out to 427
Patriot Heads
82mm throttle body
Stock MAF
Fast 36lb/hr injectors
Stock fuel pump with racetronix "hotwire" at 65PSI(?)
Base tune purchased for motor break-in

When I started with his car in the Auto VE process, it was showing in excess of 20% lean (BEN's of 1.22) even with the 15% for the Auto VE process. I didn't run it very long like this and added the 20% across the board. BEN's started showing less than 10%. After this point the BEN's have been very erratic and seems to be over compensating when I multiply to the B0101 table. After Struggling with this for several iterations, I decided to just hand smooth the table to get rid of any severe peaks/vallys, and most of the BEN's were pretty close. I did some small adjustments and the BEN's went back to 1.12 range. I don't understand why they are jumping around so much.

I am using a PLX WBO2 from the dyno which I haven't had any issues with erratic readings (I think it might be reading rich)

Our plan was to get a fuel pressure gauge and try to watch what it is doing during the tuning cycles. Here are a couple of the logs if someone could point me in the right direction. I am sure there will be requests for more info so please let me know if you need any more detail.

[mr.prick]

Which injectors are those?
It looks like just the IFR was changed, the offsets should be changed too.

The PLX output of ({EXT.AD1}*2)+10 is for EQ1=14.7 and does not match perfectly to {B3601}.
That may be one reason why BEN is "over compensating"
Setting {B3601} to 14.681005 will get it closer to the PLX PID or
you can make a calc_pid to match {B3601}
Lambda output for the PLX is ({EXT.AD}*0.1360)+0.680 if you want to go that route.

I would set {B3605} to 1.00EQ from 158F down and set {B3618} to 1.176EQ
This way commanded AFR does not doesn't hop around solely on MAP and
you can more easily control when AFR is to be richer.

[joecar]

SCP, welcome to the forum...:cheers:

Do you have FlashScan V1 or V2...?

[joecar]

Set these to in-range values:



Out of Range calibration summary: 12:21:36 am, Friday Apr 02, 2010

Engine Calibration.AIR Pump
{B0203} AIR Pump Coolant Temp Disable, was out of range when loaded.

Transmission Calibration.CARS/CAGS
{D0407} CARS Coolant Temp Enable, was out of range when loaded.

[joecar]

Set B3618 to a richer value 1.176EQ (AFR 12.44), like mr.prick said... and watch out for knock...!!

Also set B3609 to zeros... (this time is in addition to B3608).


Are you applying a transient filter to the BEN map...?

[joecar]

Can you test your PLX by running a known stoich AFR...?

Does car have NBO2 sensors...? If so, then enable B4206 and see if the WB AFR converges on 14.63 (and then remember to disable B4206 before proceeding).

[joecar]

Also log these:
GM.DYNCYLAIR_DMA
GM.DYNAIR
HO2S11 (if car has them)
HO2S21

[joecar]

Yes, see what rail pressure is doing with different loads.

This is still a returnless system, right...?

[joecar]

In log 11, the wideband AFR is not following commanded AFR at all... something is wrong...

[SCP Perf]

Which injectors are those?
It looks like just the IFR was changed, the offsets should be changed too.
Injectors are FAST brand. What do I need to adjust the offsets to?
The PLX output of ({EXT.AD1}*2)+10 is for EQ1=14.7 and does not match perfectly to {B3601}.
That may be one reason why BEN is "over compensating"
Setting {B3601} to 14.681005 will get it closer to the PLX PID or
you can make a calc_pid to match {B3601}
Lambda output for the PLX is ({EXT.AD}*0.1360)+0.680 if you want to go that route.
I can adjust {B3605} to match closer.
I would set {B3605} to 1.00EQ from 158F down and set {B3618} to 1.176EQ
This way commanded AFR does not doesn't hop around solely on MAP and
you can more easily control when AFR is to be richer.
I understand, but why does the auto VE say to command stoich in the {B3618}?


Thanks for the input Mr. Prick

[SCP Perf]

Thanks for the welcome Joecar. Sorry if some of these are stupid questions

I am using the V2 scanner

Transient filters were used per the auto VE tutorial

I will set the {B3609} to 0's - does this need to go back to 1's for closed loop?

What will setting {B0203} and {B0407} do and do I need to change them back

If setting {B3618} richer should I see knock? I haven't seen much KR with the
runs I have done so far.

Yes car has NBO2's. I will try to enable {B4206} to see if the AFR converges

Fuel System is a returnless style at the fuel rail. I believe he said there was a bypass in the tank to regulate pressure

Looking at the chart vs. some others posted, I think I see what you are saying that the WBO2 is not following commanded. Any suggestions? I am kind of leaning toward a fuel system issue, unless there are other set-up issues you see?

Thanks for all of the input.

[joecar]

Your PLX wideband should support writing the AFR via serial comms (RS232)...
FlashScan V2 supports reading the AFR via serial comms....
Doing this avoids various problems with obtaining the AFR via analog voltage (e.g. ground offsets)...
If your PLX can do this (it should), I would highly recommend it, saves a lot of trouble.

You have to see if the wideband is producing the correct output (using the STFT method).


You can leave B3609 at zero for always.

Any cells that are out-of-range will cause the PCM to do extra processing... this may or may not be good, so it's best to set them to in-range values (for always).

I saw quite a bit of KR in your logs, lasting 15-20 seconds in several places on the chart display (I'll post a pic of your log later)... it showed the sawtooth pattern that real knock shows... allowing PE to enable and to provide a sufficiently rich AFR (via B3618) will hopefully eliminate that knock...

might want to check inside the intake manifold for oil pooling (got sucked in by PCV plumbing)... oil lowers the effective octane number which allows knock more easily.

[SCP Perf]

I will try not to ramble, but here are my thoughts from your comments:

I was checking the chart a little closer and I see the KR count you were describing. It is at lower RPM (2000-2600) and higher MAP readings. In the first picture there is knock when the AFR is following commanded around 12.9, and the knock gets worse in the second pic when the AFR is not following commanded is around 14.3. The first pic also shows that when the engine is loaded and I reduce throttle position from 58% ->30% the Commanded vs actual AFR diverge. This shows up in the BENS on the third pic.

So when the auto VE process has us set {B3601} & {B3618} to 14.63 the commanded should always be 14.63. In my first picture I have a commanded of 12.96 - Is this due to the values in table {B3605} where the ECU does a rational check and takes the richer value of the two commanded(Picture 4)? I guess this makes sense regarding Mr. Pricks comments about the AF jumping around based on MAP.

Since there are points where I am getting knock at points where commanded/actual is around 12.7 should I decrease the timing in those areas until I have the VE MAP complete and start tuning for power?

Our PLX wideband is an older model used for the dyno that we temporarily wired in to the car (M-250 Model). The cars owner just purchased a FAST dual wideband set-up that we will install this week. I will try to confirm the actual readings using the STFT method - although I will have to do some reading on how to do this.:cheers:

Thanks,
Matt

[joecar]

Matt,

This is what I noticed in your log files (see pics)...

That is extended period of knock (20 seconds) on two occasions in the same log... you didn't hear it...?

Wideband seems to be working in log 10 but not in log 11.

[joecar]

...

So when the auto VE process has us set {B3601} & {B3618} to 14.63 the commanded should always be 14.63. In my first picture I have a commanded of 12.96 - Is this due to the values in table {B3605} where the ECU does a rational check and takes the richer value of the two commanded(Picture 4)? I guess this makes sense regarding Mr. Pricks comments about the AF jumping around based on MAP.

...

Our PLX wideband is an older model used for the dyno that we temporarily wired in to the car (M-250 Model). The cars owner just purchased a FAST dual wideband set-up that we will install this week. I will try to confirm the actual readings using the STFT method - although I will have to do some reading on how to do this.:cheers:
...
Setup B3605 to be flat at the stoich AFR (in B3601).
Then setup B3618 to be flat across at 12.6 AFR...
Make sure PE is set to enable with no delay (set B3609 to zero, same as B3608)...
The idea is to command sufficiently rich at load, and also like mr.prick said to have the commanded AFR stay stable while tuning on the dyno... it should only transition when PE kicks in from load increase... (be sure to apply the BEN transient filter).

Wideband is not responding as expected... to test it you could re-enable closed loop (set B3801 to Enable and B4205 to stock) and see if the wideband AFR shows stoichiometric when Closed Loop is active...

What does the wideband read in free air...?

What does the wideband read when you induce a rich condition (e.g. let some propane in thru PCV port on intake manifold while engine is idling)...?

[joecar]

Also log these:
GM.DYNCYLAIR_DMA
GM.DYNAIR
HO2S11 (if car has NBO2 sensors)
HO2S21

[Chuck L.]

NE help w/ the wb test??
http://www.youtube.com/watch?v=1mb4VmDd0ao

[WeathermanShawn]

Thats some pretty significant KR. Is that a new engine?

I guess one of the perils of tuning. Unless you are running a custom tune, you don't have a High-Low Octane Table..I.E. Adaptive Spark working for you.

Hope you get it worked out. Hate to see that kind of KR on that kind of build..Good luck..:)

[joecar]

NE help w/ the wb test??
http://www.youtube.com/watch?v=1mb4VmDd0ao+1

I had forgotten about that video...

that test is very easy/quick to perform. :rockon:

[SCP Perf]

When we were running the car, none of us heard any knocking. I am not sure what the KR is telling me other than there is knock. Does a KR reading of 3.2 mean that it is retarding the timing by that much or I need to retard it by that much? Is the level shown in the logs a severe amount? Is it the longevity of the KR or the value or both the critical item to watch out for

The software I have tuned with in the past just showed knock count as a cummulative value so this is a little different way of looking at it for me.

[WeathermanShawn]

Well normally GM's Adaptive Spark would sense the KR, then within microseconds pull the timing down until the knock ceases. With the type of tune you are doing (MAF disabled) you will be running off the Low-Octane Table (which you have set it the same as the High-Octane Spark Table). So you not the PCM has to control the spark and KR.

So you have in essence disabled the PCM's ability to control knock. So, you have to be very careful. Some of that KR was moderate and the length of time would worry me. If you are getting it, but you have adequate fueling..may not be that big of a deal. But 10-15 seconds with a lean AFR will start to do damage.

You can run a custom tune that will allow you to still have adaptive spark, but it will be hard to control with the high ECT's and IAT's your log shows.

I am just pointing out to be careful with any tuning method. The margin of error is small. But in all honesty the KR looked sawtooth and real. Thats a long time to have moderate KR (over 10-15 seconds).

Hope you get it worked out. Sounds like a nice set-up.

Good luck..

[joecar]

Not all knock is readily audible... if KR looks like a sawtooth pattern this means knock is persisting (after the PCM restores timing knock re-occurs, this repeats multiple times)... usually this lasts for a few seconds at most, in your logs it goes for 20 seconds... you have to be very careful... have someone listen using an electronic mechanic's stethoscope on each head, you will hear a dictinctive knock/rapping sound when it happens... knock is bad anywhere, but it is disastrous at large load (i.e. larger throttle with dyno loading engine down)...

find the cause of knock (if you don't believe it's real, check for headers banging chassis or something loose on the block)... but the sawtooth KR pattern typically means it's real, and not all knock is readily audible...

Oil being sucked in thru PCV (or worn rings) will lower the effective octane number which allows knock.

If the engine was running rich, or if it had been babied for some period of time, then the combustion chambers may have carbon deposits which will do 2 things that promote knock: increase compression ratio, and retain heat and glow hot.

The KR value is showing how much timing the PCM is pulling out (obtaining a final value as shown by SPARKADV)...

In this case the KR is not cumulative knock count, but the timing being pulled at that moment.

[WeathermanShawn]

Just a brief clarification on my end..

KR (timing) will still be pulled from the PCM regardless of the type of tune. If you had full functionality of the 'Adaptive Spark' feature, the timing would be pulled down closer to the 'Low-Octane Spark Table', and perhaps prevent the next KR occurrence.

+1 on the carbon deposits. You would not believe how much oil I have pulled out of the catch-can over the last 1 1/2 years..really makes a difference..

[SCP Perf]

Thanks for the great responses. We will hopefully figure out the AFR commanded vs actual with the new widband in the next day or so staying away from the high load areas. Then tackle the timing.

Thanks again.

[SCP Perf]

Well we did some more tuning this past week and I think we made some progress, but there are still a couple of issues. I finished the main VE map without any significant knock. Most of it was taken care of when the AF better matched the commanded.

When I checked with the LTFT's I was getting in the -4 to 0 range when acclerating or idling, but when coasting down it got into the -12's I believe. Not sure if the coast down part is a concern or not.

I tried calibrating the MAF sensor, but it seemed as if any changes I made with the MAFFREQ BEN's did not make much of a difference. I was still getting in the 1.1 to 1.2 range even after the first couple of adjustments. Are there any changes that need to be done to do this test from the AutoVE tuning? All I did was plug in the MAF per a previous post I found.

After fighting with this for about 5 cycles, we decided to put the car back in closed loop and do a couple of pulls to see what the AF and knock were doing. No knock at WOT, but the AF was not following commanded. It would start off about 1pt higher around 3000RPM, but get off by about 2+ around 4900RPM. It seemed like a logrithmic deviation, so I made some more adjustments to the MAF. It seems to be off still, but more in a linear fashion. I didn't like doing this, but I adjusted the commanded AF in the PE vs RPM table to get in the low 13's to high 12's for AF. This change in commanded resulted in the same change in actual. Everything seemed to be running good, and we were making decent power (520HP/508TQ) to the wheels.

We got the car of the dyno and the cars owner drove home. I got a call a little bit later saying that the car was stumbling bad around 2000RPM, but if he got in it the car would smooth out. He then called me today and said that he reconnected his wideband and the driverside was reading around 20 and the passenger side was at 14.6. Switched O2 sensors side to side and same result. I am wondering now if he has an injector issue? I asked him to switch injectors from the drivers side to passengers side to see if it follows that pattern. I started looking back at the logs and it appears that the HO2S11 V PID was having what looked like an erratic behavior. If you look at the log you can see the voltage in the 0-240 frame range fluctuates quite a bit from S11 to S21. Also, when I originally posted, we were using the bung in the drivers side for the Main VE mapping, now I believe we were using the passenger side.

Any suggestions on this? The MAF calibration and the fact that I had to "fudge" the PE values is bugging me, and I am wonding if it is due to this issue. The MAF is stock, but has been descreened if that would make a difference. (I know there are differing views on this subject)

Attached is a log file with the HO2S11 data along with the data Joecar recommended, and the final tune we ended up with.

[SCP Perf]

Another note, I tried logging the duty cycle for the injectors, but was not able to. I believe it said that it was not available, because of GM.INJPW1 was not available.

Is there another way to check this?

Thanks,

[mr.prick]

No.
{GM.INJPW1} or {GM.INJPW2} needs to be logged along with {SAE.RPM}

[WeathermanShawn]

Well the MAF calibrations would not work as you still have the MAF in fail mode.. C2901 & C2902, C2904.

I don't see LTFT's being logged. They all indicate zero.

Your O2 Voltages all look very high. Are they switching?

Maybe I don't understand B3618 PE AFR at 10.00? Is this car boosted? Is that the same PE you did the log on? I don't see it being commanded.

Is your intention to leave this car is Speed-Density Closed Loop or go back to the MAF.

Please do not be offended by this question. Are you tuning as a business or a hobby? Again no offense, but this is a difficult tune to tackle. There are a lot of issues to address. Mainly what type of tune do you want. Open or closed. Speed density or MAF.

Basically it still looks like their is a problem with the O2's, but I don't know if it is 'mechanical', or the VE Table and/or PE table is just too rich.

Anybody else want to take as shot at this. Again, OP no offense intended. I am just trying to understand the tune.

Thanks..

[joecar]

To log injector duty cycle you need to select these pids:
- GM.IBPW1
- GM.IBPW2
- SAE.RPM
- CALC.INJDC1
- CALC.INJDC2

[joecar]

I see:
- MAF is still failed, as said above by Shawn.
- DFCO is enabled (to disable: set B3313 or B3314 to 256).
- PE is not enabling (I don't see PE AFR appearing even tho FTC 22 says PE is active).
- Wideband is not responding to change in commanded fuel...

Wideband seems like it's not functioning:
- wideband AFR average value is pretty much unchanged regardless of commanded AFR...
- HO2S11/21 voltages confirm previous point...
- with DFCO enabled, when throttle is released wideband should see lean (AFR 16+), but instead it sees rich (AFR 13).

[SCP Perf]

Sorry, let me clarify, the log file was earlier during the auto VE process. I posted it just to show the discrepencies in the HO2S11 vs. S12. Also I did not have LTFT PID's selected at this point.

Also, this car was previously loaded with a tune from another person so I don't have a stock tune to compare it to. The C2901 and C2903, C2904 (no C2902) were set like this, so I was taking it back to "their" value. From the setting's descriptions it looked like they are only used to set codes, not to enable/disable the MAF.
from the C2903 description:
"With the engine running if the MAF sensor frequency is equal to or goes above {C2901} "MAF High Frequency Fail 1" this many times then DTC P0103 will set."

I attached the log from the final run which shows the commanded in the 10's. Again, I only did this because we could not get the commanded vs. actual to match. A commanded in the 10's got us an actual in the low 13's - which is not how I want to do it. Now that I know the MAF was still disable, it makes sense why we were not getting any changes with our MAF changes and it was still running off the VE table which were not set in these RPM ranges (4000 RPM Max). I can't explain why the wideband reading is doing what it is, but we have had 3 widebands in there and all of them seem to be doing similar things. After the pull the wideband goes leaner (probably too lean), so I can adjust the DFCO settings.

My intention was to return this car to closed loop MAF. I am not offended, but I am not sure what difference it makes whether or not if this is a hobby or a business? It is still my first time using the program, and there are a lot of program specific idiosyncrasies that I am still trying to learn. We bought the program to tune a LQ4 motor my father and I put into his Nomad, and came across this guy that needed a better tune. My only other EFI tuning expericence has been with Hondata software which is simplistic by comparison to EFIlive.

Looking at the SAE.generic I now see where sae.rpm is needed for the inj1pw calculation - thanks

Thanks again for the input.

[WeathermanShawn]

No I only asked so I could evaluate how to address your concerns. From my perspective (hobbyist) it is a complex tune with a number of challenging issues.

Getting that wideband working right is absolutely mandatory. I would not do anything until I got that straightened out. I have just a modest LM-1 in a bung right before the catalytic converter. I then run a serial connection to my EFILive V2. Works like a charm.

Second, I would just double-check the narrowband O2's. There are heater tests you can do vis EFILive Scan and Tune, that should tell you right away how they are functioning.

If you returning to MAF, closed-loop I think you have to look at tuning the MAF Calibration Table. There are numerous techniques, but remaining closed-loop will help you decide your approach. Once that is tuned, then you can tweak the PE Table. You have to really do it in that order. The PE Table is dependent on the MAF freq and resulting g/s airflow to have an accurate AFR.

I am pretty sure you have to adjust those MAF engine enablers back to stock in order to get the MAF working.

Again, I apologize if my question was out of line. I was just honestly trying to evaluate how basic or how complex to answer the question. Having only done this as a hobby for 1 1/2 years I have made my fair shake of mistakes. But without a working wideband and that amount of KR, I would probably attempt to re-tune in via the MAF in a very conservative manner.

Good luck..

[joecar]

What are the cam specs...?

Where did you put the wideband...?


Ok try this:

- recalculate the B4001 IFR table using the spreadsheet;
you said the injectors are FAST 36 lb/hr @ 43.5 psi;
you will need to measure the rail pressure (it should be 58 psi, you say 65 psi... measure it), see how much it varies when you do throttle snap (hopefully not more then +/-2 psi);
use this info (rail pressure, 36 lb/hr @ 43,5 psi) to recompute B4001.

- in B0101 bring all the holes up to almost the same height as the peaks,
keep in mind this is what the dyno torque curve would look like,
extend cells from 4000 rpm up to redline.

- bump up the last 2 or 3 columns of B3605 to be richer (AFR 12.5),

- set B3618 to the same all across (AFR 12.5 or EQ 1.17).

- set B3616 to this: 50% below 4000, 34% from 4000 and up.

- keep these disabled: MAF, CL, SOL (B4206), DFCO, COTP, EGR.
in the tune file above all of those are already disabled except for DFCO.

- set P0101,2,3 to "1 Trip" in C6001... (these were set to "Non-Emission" which is not failing the MAF, so it was running on B5001, but B5001 looks wrong.)

I did those, see attached file.

Then:
- on your dyno, run up slowly/steady to get good data [i.e. minimize transient throttle air/fuel effects]...
--> pay attention to see if you get knock, look at KR and also listen for knock).

- filter the BEN map and apply to B0101... B0101 is already high so it should start coming down... if not do this experiment: bump B0101 by 10% everywhere, do another dyno, BEN's should be pulling it down.

- look at resulting B0101 and extrapolate to higher RPMs... then do a quick WOT pull and see if BEN's are close, apply these to B0101 if they are not spikey.

[WeathermanShawn]

Thats a nice workup Joe.

You should bookmark that reply. Thats one of the better descriptions of how to 'smooth' and construct a VE Table..

I'll personally bookmark that one..Nice work..:)

[SCP Perf]

I will have to get the cam specs, I don't have them with me.

Wideband was put a couple of inches past the header collector.

We put a pressure gauge in before we resumed testing last week, and it stayed right around 63 - 64PSI. (FAST brand gauge) During a pull we were watching the gauge and it would not drop more than 1-2PSI

Thanks for the info, hopefully I can get the car back in in the next week and check these things out.

[joecar]

Ok, recompute IFR using:
rail pressure 63.5 psi and 36 lb/hr @ 43.5 psi...

see attached.

[SCP Perf]

No worries about the question shawn. I agree this is a difficult one to tackle for my first tune, but I have learned alot so far.

I agree I need to check the narrowband O2's, and the need for an accurate wideband is a must.

From Joecar's comments it looks like the MAF was not failing, but I am not sure why the changes we were making did not change our results. We tried calibrating this before we ever messed with the PE. Messing with the PE was kind of a last resort for now.

[WeathermanShawn]

I will have to check with Joecar..

I thought C2901 at 1 would fail the MAF..

Thats always a tricky one, because just looking at the log it is hard to tell. I'll try to get some confirmation on that one...:)

[joecar]

I will have to check with Joecar..

I thought C2901 at 1 would fail the MAF..

Thats always a tricky one, because just looking at the log it is hard to tell. I'll try to get some confirmation on that one...:)It does, but only if C6001 has P0101,2,3 not set to Not-Reported or Non-Emissions (i.e. those two will prevent a DTC... a DTC is required for failover to VE)... not exactly 100% sure about Non-Emissions.

[WeathermanShawn]

It does, but only if C6001 has P0101,2,3 not set to Not-Reported or Non-Emissions (i.e. those two will prevent a DTC... a DTC is required for failover to VE)... not exactly 100% sure about Non-Emissions.

Good point. I always kept P0101,2,3 to MIL, so I could visually see the Lamp illuminated, and then verified the DTC in the scan tool.

Any case good luck with your tune OP. Its a challenge, but thats how you learn..

[SCP Perf]

So to make sure I am using the MAF it would be best to set
{C2901}: 13000
{C2903}: 18
{C2904}: 1300
{C2906}: 6
Or something similar to these vs. relying on the Non-emissions P0101,2,3 to not fail the MAF. It will be interesting to try and recalibrate the MAF again using these values vs. what I had.

One other thing I just thought of, but when I was doing the MAF calibration, I was using the dyno to hold the engine around 3500 to 4000 RPM to get a higher count up to the 8-9K Hz. This would show the initial BEN numbers, but might not show any correction due to {B0120} set to 4000RPM. I could maybe lower this value or just run it up to a higher RPM to meet this. Does this make sense?

Thanks again,

[WeathermanShawn]

I will let Joecar comment on your first point, but I believe that is correct.

On the second point, B0120 is just telling you that after the RPM Threshold (4000), the MAF will be used in entirety for the airflow calculations. Some tuners will lower it to 400 RPM to get a pure MAF airflow calculation.

In my experience, running closed-loop with the MAF enabled..by the time you get up to 3000+ Rpms, you can successfully 'calibrate' the MAF in just the conventional way. When you hit PE Mode, and hit steady throttle, it is pretty much all MAF. The transient fueling (which will have a VE Table contribution) you usually filter out anyway.

Thats my opinion based on just my experiences. Perhaps some others can comment. But, I am basing that on your comment that you are returning to MAF enabled closed-loop. No need to make it more difficult than it needs to be, but it is always good to get various opinions..

[joecar]

So to make sure I am using the MAF it would be best to set
{C2901}: 13000
{C2903}: 18
{C2904}: 1300
{C2906}: 6
...Yes, those are the stock values... the MAF would now be enabled... there will be no current DTC's for the MAF (there may be old or historic MAF DTC's... look at the Legend to see what the characters mean).

[joecar]

B0120:
above this the MAF is used exclusively.
below this the MAF is used when throttle/airflow is steady, otherwise for transient conditions the VE is used.

If you're holding steady throttle with steady airflow, then you should be ok...
some people like to set B0120 to 400 or zero to make ensure that only the MAF is being used.

[SCP Perf]

I was able to get the car back over to my house this weekend to take a look at it. He said the only big complaint was that the car would stall when pushing the clutch in and coming to a stop, but not all the time. We took a drive to log what was happening, and it did die once.

Looking at the log, it looks like the HO2S11 and HO2S12 are not acting correctly. We hooked up my dad's truck and took a drive. The 11 and 12 "occiliate" back and forth pretty consistantely, where the camaro has 12 flatlined in the .44's and the 11 has just has some valley's. I didn't see any DTC's for the O2 sensors, but I think we need to get these reading right before we start getting the idle fixed.

Also, I loaded in another tune where I corrected the MAF fail values. After loading it in, the AFR at idle went way lean in the 20's. Went back to the previous tune, and the AFR was better. Looks like the Non-emissions was failing the MAF and that the tune on the MAF is way off.

[joecar]

Sorry, I didn't get back to you last week, I don't know what happened...:doh2:

Yes, get the front O2S's fixed.

Then, see if this helps: showthread.php?t=4661 (http://forum.efilive.com/showthread.php?t=4661)