'06 GTO E40 Inconsistent Fueling

[lsagto]

Hi all, so I have a 06 GTO with an LSA on it. Long story short, the car likes to run rich, then I modify the VE table and then its very lean. I will post two tunes and two logs accordingly, the first one (tune 13) it runs super fat and the second one (tune 14) is super lean after making some changes, although it progressively got more lean the more I drove it. Second VE table isn't pretty but more so for demonstration how this car has a mind of its own. Fuel Injector Clinic 1000 injectors, LS3 TB, its on a SD tune, more info is in the tunes calibration details. Something to note although I am confident it doesn't make a difference, the MAP I believe is on its way out. At times it reads 225kpa and wont run, have to tap it then its back to normal. But when it works, it works. Please can someone see if I am missing something but I am not understanding.
Base Tune #13.hptBase Tune #14.hptTune 13 log.hplTune 14 log.hpl

[SiriusC1024]

Change the MAP sensor. No reason not to. Then let's see what's going on.

[lsagto]

It's ordered just waiting. I mean I am sure I am wrong, but if it is reading pressure, data shouldn't be any different? To be fair I noticed the issue in the spring when I changed my injector data to the correct data off of their website. But now that I get to drive the car more I want to dial it in.

[SiriusC1024]

If you have to flick it to get it to work then something in the diaphragm mechanism is sticking or it's a bad solder joint. Could be accurate, but I doubt it. Changing it leaves one less thing to worry about.

[lsagto]

I agree, MAP sensor is supposed to be here tomorrow. Once I change it, I will post updated tune and log files.

[blindsquirrel]

I recognize that MAP linear, but not the offset. What sensor is it and where'd that linear/offset come from?

[cadillactech]

If you are using one of those modified 2.5bar MAP sensors then I believe the offset is 10.21KPA not 12.21KPA but check with whoever is selling it to you.

Will need to retune the VE table with the new MAP and values.

How are you calibrating the VE tables?

[lsagto]

DPE, only reason the offset is what it is, is because accuracy, which I changed after the fueling issue, like last week. I changed it since I knew I needed to go across the VE table again. Using their offset I am hitting boost slightly before hitting 105kpa. My pressure in KPA for my altitude is 97.7kpa. I just adjusted it accordingly. Maybe this is wrong thinking, let me know. As for tuning the VE tables, I am using a AEM 30-0334.

[cadillactech]

The values they give are for the linearization of the MAP sensors KPA to voltage reading. It shouldn't be tailored to your local baro pressure or anything like that.
I would leave it at the values the manufacture gives you.

What do you mean you are hitting boost before hitting 105KPA?

As far as your method for calibrating the VE tables, are you using a dyno? Steady state driving conditions? What kind of filtering are you doing to your data?

If you are making changes and it is overshooting you probably have bad data or data that isn't filtered correctly for the way you are gathering it. Transients will mess things up as well as decel and accel.

[lsagto]

As far as hitting boost I mean according to my boost gauge I hit boost a little before PE, but that was my idea on making the sensor accurate to my baro pressure, which I understand not to do. I am calibrating by driving on the street, to and from work and what not. The boost VE isn't that far off at all my problem lies in the VE table for cruising. Now, since posting this thread I took a step back and loaded the first tune I posted in here. That tune is now running lean, despite running super rich days before. That is where my problem lies. I am getting a new MAP to get that out of the equation.

[blindsquirrel]

What is the IAT sensor, and where is it located? Are you using the LSA's original MAT sensor in the lid as your IAT?

Non-referenced fuel pressure regulator?

[lsagto]

Correct, CTS-V lid, IAT sensor in lid, MAP sensor is referenced off the bypass, tee'd in there. Had it on the lid but the MAP sensor was acting up more there. DPE 2.5bar MAP. Fueling is a 8.1 bucket, in tank regulator, 340lph pump utilizing the stock GTO fuel pump hat, so it is returnless.

[cadillactech]

ECM Table 2402 is the minimum map table for PE to enable.

You have it set to 105kpa. Meaning PE will not enable until manifold pressure is 105KPA. If you want PE to enable sooner, make is 90KPA and watch your measured lambda versus your commanded lambda and try different values to get it to come on just when you start making boost, as there is always a little delay in enrichment hitting its target.

Same thing goes for ECM Table 2370, minimum map for boost enrichment.

I would set the both to the same KPA value. ECM will use the richer target fueling.

blindsquirrel is right ask about the IAT, you should copy the voltage axis and the temp values from the IAT2 calibration of a LSA vehicle. It didn't match up with the a CTSV file I had so you might want to double check that.

You will need some good data filters if you are just logging back and forth to work otherwise you will be chasing your tail dialing in the VE. Definitely need to adjust the MAP and IAT sensors first, set the PE so you are getting fuel when in boost and then adjust your VE tables based on your lambda error.

[GHuggins]

Once fixing the above mentioned items don't forget your cylinder charge temp biasing tables too. Then injection timing for the blower and dial in your tip temp table. Should clean up a whole lot of it after all of that.

[blindsquirrel]

With the IAT now in the lid, and not way far away from the engine at the end of the intake tube, you no longer need the compensations in the cylinder charge temp bias & filter tables - the air the IAT is now measuring is the actual temp, and it's no longer different from what the IAT measures because of ECT adding heat the sensor isn't able to pick up. Zero out the bias table, and fill the filter table with all 1's.

[lsagto]

Thank you for the suggestions. I got the cylinder charge tables taken care of, I am however confused as far as the IAT sensor values. I am comparing to the sample CTS-V tune, the IAT sensor curve is exactly the same, though the resistance column values are different.

[blindsquirrel]

I am pretty sure that GM only used two thermistors for any temp measurement, a 100k or 50k (or 43k, whatever). So the axis labels may have different incrementals which makes the cell values slightly different, but as long as you're dealing with the 100k versions in both applications the curves will be the same. If you changed the axis labels and then pasted in the other cell values you'd end up with no change that makes any difference in how it works. I'd leave it.

[lsagto]

Both the OE and the LSA are the same resistance, the curves are the same. I adjusted the tune to everyone's recommendations, and it is indeed, in my opinion, how it should operate. It has lean spots and rich spots, I am to believe that I am good to go. I will post my recent log and current (not adjusted) tune, if anyone has any more suggestions let me know. Ignore the KR.. timing is still getting dialed in. Also I did hit fuel cut RPM limit so ignore that.
23-07-16 14-49-42.hplBase Tune #16.hpt

[Alvin]

I am pretty sure that GM only used two thermistors for any temp measurement, a 100k or 50k (or 43k, whatever). So the axis labels may have different incrementals which makes the cell values slightly different, but as long as you're dealing with the 100k versions in both applications the curves will be the same. If you changed the axis labels and then pasted in the other cell values you'd end up with no change that makes any difference in how it works. I'd leave it.

I can think of earlier G8's that didn't match the traditional IAT curve or the one used in LS7's. I could be wrong.


But the OEM GTO and OEM LSA lid IAT sensor are the same curve.


If anyone else is reading the values and the axis's must be copied over.

[Alvin]

With the IAT now in the lid, and not way far away from the engine at the end of the intake tube, you no longer need the compensations in the cylinder charge temp bias & filter tables - the air the IAT is now measuring is the actual temp, and it's no longer different from what the IAT measures because of ECT adding heat the sensor isn't able to pick up. Zero out the bias table, and fill the filter table with all 1's.

Yes. I agree!