Most of my BLMs are a bit on the high side, but I don't really want to change my injector constants because there are some values that are at 128. Is the only way to do this on a $6E code to adjust the MAF tables?

 

Which ones are at 128? If the engine wasn't running for a long enough time in those cells with closed loop and block learn on, it won't learn anything.

Which cells are high?

$6E MAF isn't especially user friendly when the same airflow at different RPMs requires different fueling. The MAF tables also shouldn't really require much change, but, with my car for example, with a stock setup, the idle and low loads were rich (108 BLM etc.). This could be an injector problem, or MAF problem, or some stock calibration problem, but I'm not too worried about it - new injectors and manifold are on the shelf. I've changed the lower airflow tables a little and have seen good results, but it also seemed to create a cold idle problem within seconds of starting, which I compensated for with Open loop offset and afterstart enrichment (copied ecu item to aujm from apyp.ecu) , but I'm thinking the root of the problem is injector related.

 

Actually I was wrong. I was in a hurry for work and didn't get a chance to analyze things enough. For the most part, when load is 24-48, the numbers are in the 130s to low 140s. Once you get into more load (72-120), the BLMs are between 127 and 130, with most being 128 or 129.

I had thought I turned disabled PE (unless 100% throttle), but I was just going back through the BIN and it turns out I only disabled the "hot coolant" PE table and not the normal PE table, so it seems that my car is running a tad bit lean, and the PE is bringing it back to 128 in PE mode. I just burned a new chip with PE disabled all the way, and I'll mess with it tomorrow after school, if I end up going.

Being a tad bit lean actually makes sense. When I had the stock BIN, it was 20.8lb/hr injector constant for some reason. The APYM BIN I'm using ($6E, auto, 305) has the constants set at 19.48, and I changed them to 19.0 for the test run today. If I remember right, last time I was tuning (a few weeks ago) I ended up setting the injector constant to 18.5 to fix things. I'll probably end up doing that and then getting everything to 128, and then I'll disable closed loop to get everything at 128 in open loop, and then I'll begin to tune PE... these are the correct steps for tuning fuel, right?

 

Don't Run with PE disabled!! In one of his posts Traxion says it's one of the things you don't want to do. I'll look it up in a minute and find it. But the jist is he reccomends getting BLMs around 128 when you're not in PE and then moving the %TPS to engage PE up a bit and tune that section. But I don't think he or anyone else suggests completely disableing PE. You could fry something quick!

Also, when you go into PE mode the BLM is automatically set to 128 because you're in open loop mode. So you could be horribly lean and it'd still show 128 BLM.

 

Here is the article...
https://www.thirdgen.org/techbb2/sho...threadid=39254

Yes, its for Speed Density but many of the things Traxion says will overlap in dataloggin methods if not in tuning.

Segment partaining to you:

At this point in tuning the VE curves you will notice that you don’t have many of the higher kPa values. This is expected. In fact, I specifically stated that I avoid roads with hills. Roads with hills will allow one to tune their upper kPa VE curves. On straight roads the car lunges forward when you step on the gas (RPMs increase quickly). On roads with hills the RPMs don’t increase fast when you press on the gas. Thus, you can press on the gas on a steep hill (increasing your kPa because the throttle blades are opened more) and the RPMs will still be low. Simply put, driving uphill puts more load on the engine at various RPMs. Getting several scan tool recordings on various grades of hills is very useful for getting a handle on the upper kPa curves. However, don’t pick hills that are too steep or else you might have to press on the gas too much and thus, Power Enrichment will be engaged. Use these hill recordings to adjust the VE tables again. These recordings are only meant to get a handle on the upper kPa values. I actually use another method for fine tuning these values. The biggest problem is that you cannot press on the gas pedal too much or else Power Enrichment will be engaged. We don’t want to engage power enrichment. We want to operate solely off of the VE tables. It is extremely difficult to tune the upper kPa values in the VE tables because you have to push the accelerator pedal fairly far in order to get to the higher kPa values. This almost always engages PE. So, my method is disable PE mode in order to tune those higher values. First let me emphasize a warning here. It is very important in my method to conduct as many ‘hill tests’ as I can before proceeding with this step. You want to ‘have a handle’ on the upper kPa curve.The last thing that you would want is to disable PE and then find that you are lean in the upper kPa values of the VE tables. This can cause severe engine knock which can lead to engine damage. With that said, I don’t necessarily disable PE. I change the point at which PE is engaged. In many of the stock BINs PE is engaged anywhere from 50% to 70% throttle depending on RPM. I change these values to 85% across the board. The table that I am referring to is the ‘TPS Threshold for Power Enrichment vs. RPM’. It begins as Hex 603 and is 5 rows and 1 column (2D table). I change all table values to 85%, program a new PROM, and road test. Now it will take 85% throttle in order for PE mode to be engaged. That means that I can now test on the same inclined roads that I did previously and Power Enrichment will not be engaged. This allows me to begin to nail down the upper kPa values. I eventually change the PE tables to 90% and then collect more data, evaluate the data, and modify the BIN. I then change the values to 95% and then collect more data, evaluate the data, and modify the BIN. I then change the values to 99% and then collect more data, evaluate the data, and modify the BIN. You can see that I slowly narrow down the calibration. The one thing that you don’t want is to run lean in the upper kPa values. Patience is definitely a virtue here. When you are done testing for the day don’t forget to set your ‘TPS Threshold for Power Enrichment vs. RPM’ table back to stock settings!

 

Well its not like I'm going to floor it with PE disabled (it turns on at 100% throttle), I'll go in baby steps. This way I just don't have to change that setting each time I burn a chip. Doesn't sound like much work, but if you can do the same thing with less work, why not?

Understand completely how that works though. I'll just make sure I don't go flooring it up any big hills until I have everything sorted out.

 

another reason to consider a WB for tuning. it becomes obvious when you enter AE and PE. i am looking forward to reapproaching my CL BLM's at higher MAP/RPM. i would think on a level road with cruise control i could see if the datalog is being affected by AE. i did disable the PE by setting at 70% to work on tables b4 i had the WB. now i may not need to do that again.

ps. you can log with TPS % in your A/F log as well. neat stuff. i am sold !

 

Yeah...but WB O2s are a bit out of my pricerange for now. I've been looking at that Zeitronix (sp?) model though for like $250...that looks VERY tempting. How long have people had that running now? I'm curious as to how long they last for $250.

When I swap all the new stuff onto this motor, I'm probably going to be swapping over to SD as well. Too bad this probably won't happen as soon as I wanted though because work cut back on my hours (25% cut in hours for my department, so I lost about half of mine since I'm a PT'er). No worries though I suppose, it won't be ready for the end of this season, so I'll have all winter to do it.

 

You have a MAF car, so you cant work with the VE tables.

So, yes, you can get the lower load BLM cells down from 140 by increasing the air flow in the appropriate MAF tables, maybe table 2 and/or 3. The MAF table have flow rate in them so scan what flow rate you are at in gms/sec for each BLM cell you want to alter.

The restriction to this approach for me is that I dont deal with the source code or a hack, so I am limited to the max value allowed in each of the 6 MAF tables.

BTW: This was the approach I took with my '99 LS1 Camaro, there is only one table and the limit is 511.

 

Each of the 6 MAF table limits can be edited just like the MAF tables. Look for the scalar for each table, that defines the upper airflow limit. Just change it.

RBob.

 

Rbob,

I'm using TunerCat and 32B and 6E ECMs. Where would I find these scalar values that you mention? Recall, I dont work with the source code, dont know how.

 

In front of, or before each MAF table there are two bytes. The first of the two will be the scalar for that table. The second byte will be the number of entries in that table. Do not change the number of entries byte.

The scalar value will define the max airflow for that table. Changing the scalar term will change the end result of every entry in the table.

Here is an example from the $6E code:
RBob.

 

I take it the numbers you are talking about are the:

93
36
50
69
93
121
155
197
248

?????????????