I am have been trying to tune the VE tables by using the EFI Live v1 and a PLX wideband by following the tutorial at EFI's website. It is progressing ok. I am having trouble with the engine running real rough under light throttle acceleration.

After looking closer at the B0101/B0103 table changes, I am question if I am doing it correctly.

Does any one have a tune they could send so I can compare with what I have to make sure the tuning is going good?

I have a 98 Pontiac TA with the following changes: Yank SS3800 stall, long tube headers, no AIR, no EGR, intake lid, and no cats.

Thanks in advance to any and all who can help me out.

 

I'd give you mine, but it is too different. You can download a stock 1998 TA tune from the tune repository in the stickies. There are also modified tunes in the repository that are close to what you have. So, I am sure that a good reference tune can be located there. Good-luck

 

I have my stock tune. Its what I am comparing against and I see too many large changes that I am very suspicious about.

I don't see any modified tunes for a 98 in the EFILive repository (Holdencrazy).

 

You can use reference tunes just to look @ from 98-02. Even though the 99 & ups use a different operating system, the info. can be used as a reference. Can you post your tune file?

 

Sounds like you haven't re-calibrated your MAF table for the Long tubes....etc. Although, the EGR & air aren't that big a deal, they will affect idle.

 

Here is my latest tune file.


Was I suppose to tune the MAF before I tuned the VE?

 

Yes.

I am looking @ your tune, will post in a few.

 

You need to re-scale the MAF. Also, don't do any WOT pulls, your PE table needs to be adjusted as well.

Do you know how to re-scale the MAF? Do you have a log of this tune?

 

What does your PCV set-up look like? Has is been modified? Also, you will go back to the auto VE (unplugged MAF) after re-scaling the MAF. Just make sure that you download the stock VE tables befor you re-scale the MAF. Don't try to re-scale using the VE table in your current file. Make sure that you copy both tables (VE back-up) are the same @ related MAP & RPM.

To re-scale MAF. Car idling @ operating temps. STFT's (watch in PID log with scan tool connected) should be between -3.0 & 0. Just increase the MAF table (all frequencies 2 to 5% @ a time until you get there.

Need to make sure that the PCV is correct & no vacuum leaks first.

 

With a mild bolt on car like yours, there shouldn't be a need for dramatic wholesale changes. As mentioned above, I would throw away that tune and start from the stock tune again. Your commanded PE is 14.63 and you changed low kPa values in the Commanded Fuel in Open Loop. Have run you any datalogs and monitored LTFT's?

 

Remember that when you go back to auto VE (No MAF) that the 98 tuning software will default to the back-up VE table. This is why I metioned to make sure that the Mian table is copied to the back-up. I would suggest that you only Auto VE tune up to 70 kPa MAP @ say 4200 RPM for now. Further, because the back-up table is used in auto VE, you will have to fill in the 15,25,35,45,55...etc. VE cells in the Main table after you have run Auto VE. So, just take the average between say the 30 & 40 cells from the Auto VE back-up table & enter it into the 35 cell in the Main. That's probably why your Main VE table looks the way it does. Anyway, after you have completed the Auto VE & filled in the cells, re-calibrate the MAF table again.

Now, fill in the Main & back-up VE cells from 70 to 105 kPa up to your max RPM (6000?) with the values from the stock table & add 10% to them for the purpose of tuning. Then go to mixture (under fuel heading) & select PE Modifier based on RPM. Change the value for 4200 RPM to say .98, then reduce by .1 as RPM's increase. So, @ 6000 RPM will be .89. These are Lambda values that are richening the A/F ratio during WOT. Also, change B3613 to 65. Reduce your high & low octane spark tables to 24* from .88 through 1.00 Grams/Cylinder.

Now log some WOT runs paying close attention to A/F ratio & knock reduction. I'd say that you are looking for 12.5-12.8: A/F ratio from 4000-6000 RPM. Make the first pull to say 5400 & check the A/F & knock reduction to make sure that you are in the ballpark or at least not lean w/ knock, then go up from there. Change the PE modifier based on RPM in order to change the A/F ratio (higher numbers are leaner, lower numbers are richer). WOT uses the PE table(s) during WOT w/ the VE table as a reference. Where as non-WOT uses the VE table. Once the WOT A/F is dialed in, then you can increase the spark that was previously reduced until you see knock, then reduce until the knock is gone.

Make sure that the VE table cells that exist in the WOT area are the highest & close to accurate. As mentioned, they are used (back-up VE) as a reference & will be of greater use upon a MAF failure.

Hope this helps & should get you on your way.

 

My PCV setup is stock 98. I have not modified it as my TA doesn't use any measurable amount of oil.

I have the stock tune saved, so it is easy to start over and adjust the MAF first.

Its too early to digest everything (love ealy tele-cons with Japan). Thanks for the help and I will post my progress.

 

I am trying to get ready to recal the MAF and have a question.

Do I recal with a stock closed loop setup or a sd ve setup? I am not to clear on this point.

 

First w/ stock. Then again after you have run the SD VE. This is what I mentioned above. It may sound silly, but it's best to start from scratch. That's why I say start w/ the stock Ve table first.

Also, post up once you get to the WOT PE tuning. The values I referenced above were based on trying to be safe from where you were. So, once you have the tuned MAF & a fairly accurate VE table, post the tune & all of us can then comment regarding the PE based on RPM values. Ideally, they will want to be in the .887 lambda range w/ everything else MAF & VE being correct, but we'll have to see where you are. Also, post the log file used to create your VE table.

It will be days or weeks before you get to this point, just wanted to comment on where you'll be going next.

 

I have another question. When re-calibrating the MAF, do I idle in gear or out of gear?

In gear, my STFTs are 0.0. In gear, the STFT's range from 0.0 - 2.6.

 

It's the difference between your in-gear & P/N airflow tables during idle. Your STFT's are close enough either way.