E67 VVE Tuning Issues....Some Fundamental Questions

[four_by_nut]

I'm helping a buddy tune an E67 Gen4 ECU that came out of a 2007 Saturn Ion (2.4L Ecotec). It's boosted, up to about 14psi. For refernece, I've successfully tuned my 2007 2.2 ecotec up to about 6psi of boost. But I've run into an issue on this tune of his motor.

Some changes I've made to the tune (to get you oriented with the current setup):

- This engine is in a rock crawler/buggy. Only the engine is "at play" here.
- Running a small turbo with waste gate set around 14psi.
- Engine is upgraded with 60lb/hr injectors.
- Running a 2bar MAP sensor. (I've updated the tune to match the offset and linear for this new MAP sensor)
- I've disabled the MAF. IAT is still active in the sensor. Planning to stay with a speed density tune; no MAF tune.
- I've extended the MAP estimation out to 205kPa
- I've extended the VVE table out to 205kPa
- I've got the VVE zones remapped to be pretty consistent across the table.

Here is what I see is happening. I started with the stock tune and then added the boosted range. When I flash this in, it runs way rich at idle and anything above that. So I drop everything down using changes to the VVE table until I get idle around 14 AFR. But when we stall torque it, it goes richer and richer and richer as we get into the throttle more and more. And it does the same when we drive it. By "rich" I mean it will be nearly 14.7 at idle and when I get close to 95kPa, it's about 30% rich. So now you are probably reading this and say "Well....just drop your VVE values at the higher load/rpms". well......what I find is that at idle a VVE value of around 640 gives me nearly stoich, but at 1400rpm and 90kPa, a value of 658 ends up 30% rich! WTF?!

Clearly, I am missing something fundamentally wrong. I've done a LOT of research and reading and have a couple of questions that might help get me there.

1) I've been tuning with the HPTuners released version 4.10.4. Is this a problem when trying to do VVE tuning in the editor on an E67 Gen4 computer? I caught a little "tid bit" in a post that perhaps you have to use the beta version to get the coefficient calculations to work correctly with this ECU. True?
2) I'm still trying to understand the "Manifold Vacuum Boost" OS patch. I've tried a tune with and without this applied (yes, I did a full load after the changes). Seems to make no difference in my case. I still get the same results I described above. My understanding is that you use this patch if you want the other functionalities available with the patch update but don't plan to go boosted; you want to just keep using injectors and MAP that you currently have stock. True? Or is there more to it? And does this patch really have an effect in all ECUs that it is available? I'm thinking no, because when I changed it, it made no difference.

I know there is a TON to creating a tune. So let's just start with the two questions I've asked, given the info above, and see if that gets me there. Like I said, I think I'm missing some fundamental issue. Just not sure what that is.

Thanks in advance....

[smokeshow]

Hard to say without data or a file. Might need to re-zone the VVE and re-populate the coefficients. Might be something in the dynamic calculation. Might be something you missed.

[383_Stroker]

Attach a Tune and a Log if possible.

Is the commanded AFR 14.7 the whole time or are you getting into PE?

[four_by_nut]

Ok. I think I'm an idiot. I'll admit it. I messed up setting the DTC P0103 to "MIL on First Error". I had it set to "No Reported Error". Sooooo........I wasn't failing MAF and dropping into SD like I thought. Duh! And I had not calibrated MAF at all with this since we added a turbo and I was going to stay SD with this tune. Totally explains what it's doing/acting like. Gonna try that change tonight. I fully expect this solves my issue. I'll report back.

Sorry to post my question and then realize a "rookie" mistake later. But I'm pretty sure this is my error.

[four_by_nut]

Ok. The change to the DTC didn't solve the problem. And I confirmed it DID set the DTC for P0103. Attached is the tune and a log file where I was just stall torquing it up to just about into boost. This thing has a really small turbo. So it gets into boost very early.

You will notice, at idle it's lean. As I step in a little it goes rich, a little more (around 65kPa), it goes lean again, and then around 95kPa it goes almost 30% rich. And you can see from my VVE table, that is NOT how I have it programmed. It suggests that it wants nearly the same VVE value at 95kPa as at idle.

See if you guys see what I'm missing.

Tune 3.hpt
Tune 3.hpl

[smokeshow]

I'd be paying close attention to camshaft phase angles, particularly exhaust. This is where you will find out how deep the rabbit hole can go.

[four_by_nut]

I'd be paying close attention to camshaft phase angles, particularly exhaust. This is where you will find out how deep the rabbit hole can go.

I would have thought that through the N/A range, this wouldn't be any different than stock. I would have thought it would act the same as stock and be at least close. Are you saying that even though I haven't changed anything to do with the the camshaft timing/angles, it's gonna be different now that I've bolted a turbo on? I know when I tuned my gen 3 computer for my 2007 cobalt motor, the N/A range was still pretty consistent. It needed some adjustment but I spent most of my time in the boosted range. This one seems to be all over the place all over the map.

I will look to record cam shaft angles and hope that rabbit hole isn't deep! Else I'm gonna take the Blue Pill!

[smokeshow]

The calibration will, absolutely. You now have a restriction placed in the exhaust. And your issues are occurring right as the exhaust cam calibration shows a huge ramp in phase angle. That alone would make me dig into it.

[four_by_nut]

Aaahhhhh. Ok. I'll look into that! thanks. Will let you know what I find.