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I've learned alot about these systems since installing EFILive in the LLY (well, the onboard PC anyway). Just thought I'd share a few thoughts.
1. The main power setting comes from a desired injection quantity (per cycle) expressed in cubic millimeters. There is a table in the control that tells the injectors how long to stay open for a desired fuel amount, at a given fuel rail pressure.
My aftermarket tuner changes these tables in certain regions of fuel pressure and desired qantity. That means more fuel will flow, and the computer won't know. E.g. it wants 50 mm3 and gets 60 mm3, but it thinks its going to be getting 50, and that's used in all other calculations...
So, if the transmission looks at fuel quantity for info on how hard to hold the plates, it'll use a wrong number. If the engine estimates torque from fuel injection flow, for use by the trans, that'll be wrong too. That explains why the trans has a conniption when I change the tune (using this method).
It's logical that if you wanted to calculate fuel mileage, you look at the injection amount per cycle. RPM/4 tells you how many cycles there are per minute. From that you can get fuel flow. From the VSS, you can calculate mileage. Of course, if you're using 50 in the calcs, and 60 is really flowing, then the mileage calc will be wrong, in favor of higher mileage calculated.
2. Question, in the boost tables. There is a vane position minimum (max opening). No problem. That's the most it will open as a function of RPM and fueling. There's a Maximum vane position table too...the most it will close as a function on RPM and fueling. But, what is the table "Turbo Vane Target Position"? I thought it was varying vane position in order to reach a target boost pressure? Like, it would stay at the maximum setting (most closed), until boost comes up, then opens a bit to hold it at the desired boost value. What gives? Or is the target where it stays, until modulating, bound by the min and max? I'm going to have to add vane pos to my dashboard and watch it as I drive to see what it's up to.
In the idle range of RPM and fueling, the max and min are both 58%. I guess that means it's locked at 58% at idle.
3. MAF. There is a table of expected airflow vs. RPM and fueling. But there is a temperature value of 150C above which the collant must be in order to test airflow using this table. That basically means the table is not used. So, since the MAF appears nowhere else in the fueling calcs, the only use of the MAF sensor is for testing the EGR? OF course, you can look at it move around, but it does nothing.
4. Fully disabling EGR is easy. There are min and max RPM values for enabling EGR. Stock they are 200 min and 3500 max. I changed them to 4000 min and 4100 max. No more EGR. I also disabled the diagnostic test, So no more trouble code.
5. The speed limiter is obvious. Between 177 and 193 km/hr, it cuts off fueling. Change the value at 193 to 120 mm3, and no more speed limiter.
6. Interesting enough, there is little modification of fueling, as a function of throttle and RPM. There is a table, and the resulting value is modified if in engine protection mode, or overheating, but other than that, that value gets injected. The fuel pressure, and timing vary with ECT, BARO, fuel temp, etc...but not the fueling rate itself. I was surprised anyway.
7. Is the value in injection timing, the start of the pilot, with the main injection coming "Injection timing after pilot" later? For the base timing, negative is after TDC, and positive is before TDC, right?
Timing appears very conservative. At idle, the base timing is actually after TDC. It also looks like the timing is almost always after TDC for the main. This has to be for NOX, and means there's lots of room for improvement in terms of economy.
Lots to learn. Nice job on the program, BTW.
1. The main power setting comes from a desired injection quantity (per cycle) expressed in cubic millimeters. There is a table in the control that tells the injectors how long to stay open for a desired fuel amount, at a given fuel rail pressure.
My aftermarket tuner changes these tables in certain regions of fuel pressure and desired qantity. That means more fuel will flow, and the computer won't know. E.g. it wants 50 mm3 and gets 60 mm3, but it thinks its going to be getting 50, and that's used in all other calculations...
So, if the transmission looks at fuel quantity for info on how hard to hold the plates, it'll use a wrong number. If the engine estimates torque from fuel injection flow, for use by the trans, that'll be wrong too. That explains why the trans has a conniption when I change the tune (using this method).
It's logical that if you wanted to calculate fuel mileage, you look at the injection amount per cycle. RPM/4 tells you how many cycles there are per minute. From that you can get fuel flow. From the VSS, you can calculate mileage. Of course, if you're using 50 in the calcs, and 60 is really flowing, then the mileage calc will be wrong, in favor of higher mileage calculated.
2. Question, in the boost tables. There is a vane position minimum (max opening). No problem. That's the most it will open as a function of RPM and fueling. There's a Maximum vane position table too...the most it will close as a function on RPM and fueling. But, what is the table "Turbo Vane Target Position"? I thought it was varying vane position in order to reach a target boost pressure? Like, it would stay at the maximum setting (most closed), until boost comes up, then opens a bit to hold it at the desired boost value. What gives? Or is the target where it stays, until modulating, bound by the min and max? I'm going to have to add vane pos to my dashboard and watch it as I drive to see what it's up to.
In the idle range of RPM and fueling, the max and min are both 58%. I guess that means it's locked at 58% at idle.
3. MAF. There is a table of expected airflow vs. RPM and fueling. But there is a temperature value of 150C above which the collant must be in order to test airflow using this table. That basically means the table is not used. So, since the MAF appears nowhere else in the fueling calcs, the only use of the MAF sensor is for testing the EGR? OF course, you can look at it move around, but it does nothing.
4. Fully disabling EGR is easy. There are min and max RPM values for enabling EGR. Stock they are 200 min and 3500 max. I changed them to 4000 min and 4100 max. No more EGR. I also disabled the diagnostic test, So no more trouble code.
5. The speed limiter is obvious. Between 177 and 193 km/hr, it cuts off fueling. Change the value at 193 to 120 mm3, and no more speed limiter.
6. Interesting enough, there is little modification of fueling, as a function of throttle and RPM. There is a table, and the resulting value is modified if in engine protection mode, or overheating, but other than that, that value gets injected. The fuel pressure, and timing vary with ECT, BARO, fuel temp, etc...but not the fueling rate itself. I was surprised anyway.
7. Is the value in injection timing, the start of the pilot, with the main injection coming "Injection timing after pilot" later? For the base timing, negative is after TDC, and positive is before TDC, right?
Timing appears very conservative. At idle, the base timing is actually after TDC. It also looks like the timing is almost always after TDC for the main. This has to be for NOX, and means there's lots of room for improvement in terms of economy.
Lots to learn. Nice job on the program, BTW.
