2.4L LE5 E67 GMVE Tuning

I have been working off and on (mostly off), on tuning my 2007 G5-GT. I originally had the car tuned by a local before I got my HPT and really got in to tuning. When he tuned it, he only changed the MAF as at the time, parametric VE were only topics of discussion.

I have now been working on tuning VE with the EQ<>VE application and have been able to get some results. The issue that I have is that as a new tuner I do not know what all of the table’s control. I have followed some guides to understand how to obtain my commanded AFR when adjusting VE, but I am not thrilled with the results. These guides recommend that you remove enrichment values from Open Loop EQ Ratios and make them a flat 1 across the board. After tuning to these values cold start then becomes an issue since these table are there specifically for cold start purposes. Putting these values back to stock after completing VE would then have an adverse effect on what I was able to obtain while tuning my VE so that is something I would think I would not want to do.

What would be the adverse effects of leaving the EQ Ratios stock when tuning VE? I know that they would be adding more fuel, but since I know this is a constant, it would be calculated in to my AFR error percent.

Attached is my tune after tuning VE, Config that I use for scanning and log with that tune installed after setting back to Closed Loop.

Well, no replies in this thread so I guess there are not any takers here. So I may just turn this in to my blog about tuning project.

I did some more tuning this past Saturday after posting. I started over again with my VE as I felt that I had missed some things and wanted to try to tune with my Open Loop EQ Ratio tables set as they came from the factory. Well, I spent a lot of time doing this and was able to resolve my cold start idle issues, but I believe that I may have missed turning off my LTFT's or STFT's or DFCO or CFCO or COT.

After that I decided that I am going to start writing my own paper on a tuning guide. I found that there is not a complete comprehensive guide around here and I was having to reference multiple in order to complete what I need. So off I have started to complete a Gen IV E38/E67 GMVE Guide. I started with someone else’s format so I need to get their permission to continue before posting publicly, but I believe it will help several people out.

Now on to tonight’s events, through studying and searching, I have found it documented in a few places that the Stoich for the fuel that I am using should be 14.13:1 AFR. I took one of my tunes and went in and change my Stoich AFR table in the 0.00 column to 14.13. Well since I have my precision set to 0.00000 it pushed it down to 14.12988 which I can live with since it is very close to 14.13.

http://www.hptuners.com/forum/attach...1&d=1267585470

So I went out and started tuning to this new AFR with my stock Open Loop EQ Ratio tables and this is what I have been able to get my AFR Error % down to.

http://www.hptuners.com/forum/attach...1&d=1267586287

I know it still has some work and I have not made a correction after this log yet since each one takes about thirty minutes to complete, logging then using EQ<>VE, smothing and then pushing back in to tune and having to do a write entire since these ECM's will not alow you to just do an update.

Also attached are my latest tune, config since I changed it for MAF tuning and to increase the precision on AFR Error and latest log file.

Any comments are welcome...

-Don

So, it has been a couple of years since I started this journey of trying to tune my LE5 E67 and my outcome has been less than stellar. I started back up again a few weeks ago and started some threads in some different sections as I thought it might reach a few more people, but alas I did not get any responses.

One thread I started here speaks to an issue I had while tuning just based on wideband AFR. I was getting opposite results from AFR vs. STFT and when I made a change it just exacerbated the issues. I changed my tuning technique to use Lambda instead of AFR, but I don't really know if that is what solved that issue. This may have just been a simple case of setting up the values of my AFR Error and Histogram incorrectly.

From there I started working on my VE. Of course this is a virtual VE, or parametric VE or a five dimension VE, whichever you like. I did not lock my cam phases to zero, but here in Orlando temps are pretty consistent and there are really no hills to speak of, so driving is always really the same thing. I went through and got my VE nice and smooth and AFR error to +-2%. At this point I was also tuning with PE disabled and being sure not to run it hard. I was tuning in open loop speed density and things seemed to be coming along nicely.

http://www.hptuners.com/forum/attach...1&d=1339722612

This is where I started to have issues again. I now turned on PE, but still have the MAF disabled and running open loop. On my way to work I have one on ramp where I can let the cars space out and then get on it to bring in PE and on the way home I have about two places I can do the same on surface streets. I found that even though my car was going in to PE, it was still not delivering enough fuel. I tried several times to use my lambda error and raise my VE table at 99kPa, 2800rpm and up, to really raise it up. No matter how much I bring it up, it appears that without the MAF the ECM will still not recognize how much air the engine is using. So this leads me to the conclusion that if you have a MAF failure, you still do not want to get in to PE very much as it seems as though the ECM will not support it.

http://www.hptuners.com/forum/attach...1&d=1340318387

I am now at the point I am going to go back and correct my VE once again, with no PE. Once I have that dialed in, I am going to disable VE and dial in my MAF, agin with no PE. I will then turn on PE, MAF only and see if the ECM will operate this way. If not then I will try PE with blended and go from there as at that point I will know I have my VE and MAF in line.

I have also ordered and just received some graduated cylinders. I went ahead and bought a three piece set 25ml, 50ml and 100ml. I will be testing for the amount of Ethanol in my fuel. I always fuel up my cars at the same two stations and always use 93 octane. I am hoping that I can come up with a better estimated stoich as if you read my earlier posts, I was using 14.13, but of course with an AFR converting lambda gauge, that is unobtainable. I since started just using the factory preset of 14.70.

I have also just this week ordered a LSJ M62, lower intake manifold, intercooler pump, stock LSJ injectors (those will not even get used at all), idler, tensioner and several other miscellaneous pieces. I am hoping over the next couple of months I can get all the pieces together to install on my car. Of course I will have to start all over again with the tune. I am thinking that I will probably need to buy the Siemens Deka 60lb injectors, as I know I won’t be happy until I pulley down to around 3”.

your ethanol test may have a value but every time the truck fills the in ground tanks the values can fluctuate. 93 octane with 10% e is shitty and innacurate. basically the sticker is there to notify people it can have up to 10% e blended in.


im pretty shure the m62 is a 3.2" pulley and 42lbs should be good until you hit the 2.9" pulley. any lower than that the 60's would definately be required along with some cooling mods to keep charge temps down.

Okay mister tdabbs you sure like to do things a very strange way. If you tune in open loop you know the command afr is not always the stoich you choose right? Also if you close in closed loop using the ltft+stft you will have way less problems. If you want to tune sd then go for it but use it for idle cruise and partial throttle. Use the maf for wot it will work out way better.

Quote:

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Originally Posted by cobaltssoverbooster

your ethanol test may have a value but every time the truck fills the in ground tanks the values can fluctuate. 93 octane with 10% e is shitty and innacurate. basically the sticker is there to notify people it can have up to 10% e blended in.


im pretty shure the m62 is a 3.2" pulley and 42lbs should be good until you hit the 2.9" pulley. any lower than that the 60's would definately be required along with some cooling mods to keep charge temps down.

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I understand that the Ethanol test will vary by some degree, but since I always purchace fuel from one of two stations that always use the same supplier (primary is Sunoco and secondary is Hess) I should be able to find a happy median.

Yeah, the stage 2 injectors are 42lbs, but I only want to purchase them once. I don't recall from reading if the E67 ECM can take the values of the 60lb without having to scale everything. If it can't, I may rethink this and just use the 42s and only pully down to their limit.

Quote:

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Originally Posted by laser_racer

Okay mister dtabbs you sure like to do things a very strange way. If you tune in open loop you know the command afr is not always the stoich you choose right? Also if you close in closed loop using the ltft+stft you will have way less problems. If you want to tune sd then go for it but use it for idle cruise and partial throttle. Use the maf for wot it will work out way better.

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I don't really consider myself as doing things a strange way, but I am very OCD and must have things as close to perfect as possible. I understand your comment about tuning in open loop and the commanded AFR not being the same as stoich. This is why I have converted everything over to lambda as E10 stoich AFR 14.13 = lambda 1, so does pure gas AFR 14.68 = lambda 1.

Yes, as I wrote above, I have found that open loop speed density will not react correctly for PE. Do you know if an E67 will react correctly in open loop pure MAF for PE?

Just FYI, this is what it looks like running open loop speed density with power enrichment. Pretty FUGLY.

http://www.hptuners.com/forum/attach...1&d=1340335065

I still run 14.7 with e10 the amount of ethanol is so minute there really is no reason to change it. 60's will require complete injector value change.

Laser correct if wrong but u saying this right:
Fail maf, tune idle to midrange hmedium load using fuel trims. Reengage maf and tune maf with pe active to get final results

Quote:

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Originally Posted by cobaltssoverbooster

I still run 14.7 with e10 the amount of ethanol is so minute there really is no reason to change it. 60's will require complete injector value change.

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I understand they require an injector value change (done that before), but I believe 60lb injectors may not be supported in the O/S and require everything else to be scaled to compensate.

Quote:

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Originally Posted by cobaltssoverbooster

Laser correct if wrong but u saying this right:
Fail maf, tune idle to midrange hmedium load using fuel trims. Reengage maf and tune maf with pe active to get final results

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Well you actually have to tune full maf table or fuel trims will be every wheres since you cant go just sd on bottom end. Once the bottom end is tuned on both tables blend them for under 3k rpm then just go straight maf. Sorry if I get confusing I lose my train of thought lol. Also for the 60 question there isnt a problem doing the 60s for your car I did a g5 2.4 and 2.2 with them before. I will say if you just tune closed loop and do maf for wot your brain will stop hurting. I feel you on the ocd I get it working on cars.

Don’t you have to know your fuels stoich so that your power enrichment will calculate correctly?

Correct me here if I am wrong, but if your ECM thinks that your fuel stoich is 14.7 but is really 14.2 and you have tuned so that your LTFT+STFT error is around +-2%, when you calculate your divider your commanded PE will actually be leaner than you like. Your narrow band O2’s cannot calculate AFR, they only know stoich or lambda. Therefore when you tune based on LTFT+STFT error and your ECM thinks your fuel is 14.7, you will actually be starting at .5 AFR off at 14.2.

If you want your power enrichment commanded to be 12.3 AFR (corrected for e10), you take your stoich and PE divider to be that value 14.2/1.154=12.3. Now that you have tuned with an unknown fuel stoich value, which could be 14.2, your equation now becomes 14.7/1.154=12.74, assuming you have adjusted your PE divider for e10 to compensate, but everything now is just a guess.

Well if you read pump it says may have up to 10% not that it does. Also the narrow band is looking for lambda one the stoich has nothing to do with fuel trims. If you want to use say 14.3 as stoich you take that number and divide it by what you want and then you have your command afr.

Here is the results of my Ethanol testing in my fuel. I went to my local Sunoco station that I typically fuel up at. I pumped one gallon of gas in to my car and then one gallon of gas in to my clean dry gas container. The reason that I did this is because, as most stations, there is one fill hose for four grades of fuel. I brought the gas home and transfered 50ml of the gas in to my 100ml graduated cylinder. To avoid over filling with water, I filled my 50ml graduated cylinder with water. I then transfered the water to the 100ml cylinder and noted that I had lost about 1ml during the transfer due to the water adhering to the glass. I then shook the container and noted another loss of 1ml due to adhesion to my plastic cover sheet and glass cylinder.

http://www.hptuners.com/forum/attach...1&d=1340594269

Results were 54ml of water and 44ml of gas. This is about as close as it gets to 10% ethanol.

I am adjusting my Stoich AFR to 14.12988. When plugging this stoich in to my PE table, it appears that the ratios still apply. Attached is my simple spreadsheet for calculating PE if you care to take a look at the result/RPM.

correction... 2 ml loss. check out the meniscus :)

lol dude your just a little too ocd for me i had to pick you on it.

Edit... damn i went back and reread it... you did specify 2 ml loss....

Still though everyone else here runs e10 pump gas at an afr of 14.7 if he wants to run richer and loose mpg that is his opinion

Quote:

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Originally Posted by cobaltssoverbooster

Still though everyone else here runs e10 pump gas at an afr of 14.7 if he wants to run richer and loose mpg that is his opinion

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I don't see him running his 14.1 really messing with his gas mileage much unless he is running it in open loop. If it is in closed loop the car can careless what kind of fuel is in it unless it can't make it to lambda 1.

I would agree that several here in the 4 cylinder section tend to not adjust their stoich point. Maybe that is due to the less expense of rebuilding a four cylinder vs. a V8 after lifting ring lands or burning holes in pistons or valves.

A couple of examples;
Any special consideration for e-10?
Retune for E10?
VE/MAF Tuning and E10
AFR for todays Car with ethenol?

I haven't seen to many destroyed engines because of the stoich value being set to 14.7. I haven't looked at your links but a lot of the v8 people run speed density and that will require the right stoich so car doesn't die. Running in closed loop the car will always keep its self adjusted to stay safe.

He's changing the stoich value though so for 3/4 of the maps he will run 14.1 which is more fuel I think he's gonna loose 2 mpg avg for no reason but then again u know more about it than I.

If anything, fuel mileage should increase. As laser racer stated above, fuel trims will correct fueling to stoich. What I am doing is actually calibrating the ECM to the fuel and the engine so that it does not continuously have to run trims to offset an incorrect fueling map. The reason that I say it may increase is that the ECM will not have to make adjustments to fueling from cell to cell. This should add to the efficiency, but I really cannot complain as I typically get an average of 30MPG with this car.