Looking for some help with a modified program
Posted: Mon Feb 13, 2017 1:32 pm
Been working with Robert Saar to get my truck running-he wrote a patch to allow the usage of 2-bar map sensors with the 16196397 PCM. He's said he mostly just copied his successful work on the $A1 code, and while the code works fine in $A1, I haven't got things working properly yet. He seems to have gotten busy with life and work, so I haven't been able to get the pickup truck running. I'm hoping to find someone here who can help me finish debugging and get things going.
Here's the details:
PCM is an early flash-based, dual 68HC11 Delco, for the 1994 F-body manual V6. it is similar to, but not a clone of, the LT1 computer from the same year. Flashing, datalogging, TunerproRT support, all that is there. I built an F-body 3.4L V6 engine to fit in my S-10 pickup truck, complete with 2006 Malibu aluminum heads/intake, (same architecture engine, nothing huge there) and just because someone dared me to, I fitted the supercharger from an L67 engine to the top.
The pickup used a 2.8L version of the same engine, and the 1228062 ECM running $4E was the original computer. I stripped the wiring harness and computer from the S10, and used the Camaro computer and wiring harness, to match the engine. Everything went well, and the engine has been broken in on a kludged program. Basically, using the 2-bar MAP sensor and 36lb/hr L67 injectors, but having the computer use the 1-bar MAP code and 17.50lb/hr stock injector settings. The engine ran fine this way, fuel and spark were perfectly acceptable for break-in.
Now, after fighting with bricked PCMs, bad tunerpro data, and finding out in the end it was all due to a bad USB-to-ALDL cable, I've gotten far enough to find out that the PCM isn't reading the MAP sensor while the engine is running. Basically with the patched code, the MAP sensor updates when I key-on, updates on cranking, but as soon as the engine transitions to "running" the MAP sensor stops updating and tunerpro reports a fixed MAP value. It's the correct value, but the computer appears to not be polling the sensor anymore. Not really gonna run too hot that way.
https://www.youtube.com/watch?edit=vd&v=2k2wm2K4mc0
The above link was actually a video I was taking for the writer of Tunerpro, to show the data errors-this has since been fixed. It also shows the MAP sensor issue, which is why I linked it here.
The PCM works fine if I change the code back to the 1-bar factory code and sub in a 1-bar sensor...for that matter if I just chop the injector size in two and use the 2-bar sensor it works fine, but MAP readings are almost halved. Too much stuff relies on the MAP value in the PCM to actually try to drive it that way, so this isn't really an option.
Here is the stock BIN, the ADX, and the XDF file for tunerpro that includes both a known-good-working bugfix patch (the Revision 3.01 patch) and a Possibly-Might-Work-Great 2/3 bar Boost patch. If anyone here can take a look and see if there is anything that could help figure out why the PCM isn't updating the MAP sensor when patched for 2-bar map sensors, it would be *greatly* appreciated.
To use the patch, open the bin in Tunerpro, select the XDF and under "Patches" select the patch and choose "apply patch". This will apply the patch, and modify the BIN file for you. I have not dissasembled the BIN file yet, so I do not know exactly where it's patched, but I do have a description of how the patch works.
He changed the code to allow the user to set a few fields defining the MAP sensor range (so you can input the correct numbers for a 2 bar or 3 bar sensor), and then also emulates the 1-bar signal for the T-side transmission control code. MAP information is passed over the SPI bus(both an emulated 1BAR signal for T-side usage and the raw 2/3BAR signal for the end-user) since there isn't enough space on the T-side for more emulation code. speaking of space, after all has been added on the E-side, there are two sections of free space, one is about 900 continuous bytes, the other is about 2800 continuous bytes. The VE and Spark tables have been expanded a bit, and each has a second table added for 100-300KpA ranges. (Main VE and then Main VE Boosted, Main Spark and Main Spark Boosted)
The only quirk so far is that the barometric update function may require disabling/severe limiting(since baro updates happen with high throttle/low vacuum, when the blower does its magic). I do not know what's going on here, so not sure what this will require, if anything.
I'm a novice programmer, but I have worked with Atmel stuff before-just not the 68HC11, which is what this PCM uses. (two of them, actually) I will provide as much data/testing as I can, and if needed I can send a socketed PCM and harness plugs and wiring pinout. (I've got four here, they're cheap on Ebay!)
Here's the details:
PCM is an early flash-based, dual 68HC11 Delco, for the 1994 F-body manual V6. it is similar to, but not a clone of, the LT1 computer from the same year. Flashing, datalogging, TunerproRT support, all that is there. I built an F-body 3.4L V6 engine to fit in my S-10 pickup truck, complete with 2006 Malibu aluminum heads/intake, (same architecture engine, nothing huge there) and just because someone dared me to, I fitted the supercharger from an L67 engine to the top.
The pickup used a 2.8L version of the same engine, and the 1228062 ECM running $4E was the original computer. I stripped the wiring harness and computer from the S10, and used the Camaro computer and wiring harness, to match the engine. Everything went well, and the engine has been broken in on a kludged program. Basically, using the 2-bar MAP sensor and 36lb/hr L67 injectors, but having the computer use the 1-bar MAP code and 17.50lb/hr stock injector settings. The engine ran fine this way, fuel and spark were perfectly acceptable for break-in.
Now, after fighting with bricked PCMs, bad tunerpro data, and finding out in the end it was all due to a bad USB-to-ALDL cable, I've gotten far enough to find out that the PCM isn't reading the MAP sensor while the engine is running. Basically with the patched code, the MAP sensor updates when I key-on, updates on cranking, but as soon as the engine transitions to "running" the MAP sensor stops updating and tunerpro reports a fixed MAP value. It's the correct value, but the computer appears to not be polling the sensor anymore. Not really gonna run too hot that way.
https://www.youtube.com/watch?edit=vd&v=2k2wm2K4mc0
The above link was actually a video I was taking for the writer of Tunerpro, to show the data errors-this has since been fixed. It also shows the MAP sensor issue, which is why I linked it here.
The PCM works fine if I change the code back to the 1-bar factory code and sub in a 1-bar sensor...for that matter if I just chop the injector size in two and use the 2-bar sensor it works fine, but MAP readings are almost halved. Too much stuff relies on the MAP value in the PCM to actually try to drive it that way, so this isn't really an option.
Here is the stock BIN, the ADX, and the XDF file for tunerpro that includes both a known-good-working bugfix patch (the Revision 3.01 patch) and a Possibly-Might-Work-Great 2/3 bar Boost patch. If anyone here can take a look and see if there is anything that could help figure out why the PCM isn't updating the MAP sensor when patched for 2-bar map sensors, it would be *greatly* appreciated.
To use the patch, open the bin in Tunerpro, select the XDF and under "Patches" select the patch and choose "apply patch". This will apply the patch, and modify the BIN file for you. I have not dissasembled the BIN file yet, so I do not know exactly where it's patched, but I do have a description of how the patch works.
He changed the code to allow the user to set a few fields defining the MAP sensor range (so you can input the correct numbers for a 2 bar or 3 bar sensor), and then also emulates the 1-bar signal for the T-side transmission control code. MAP information is passed over the SPI bus(both an emulated 1BAR signal for T-side usage and the raw 2/3BAR signal for the end-user) since there isn't enough space on the T-side for more emulation code. speaking of space, after all has been added on the E-side, there are two sections of free space, one is about 900 continuous bytes, the other is about 2800 continuous bytes. The VE and Spark tables have been expanded a bit, and each has a second table added for 100-300KpA ranges. (Main VE and then Main VE Boosted, Main Spark and Main Spark Boosted)
The only quirk so far is that the barometric update function may require disabling/severe limiting(since baro updates happen with high throttle/low vacuum, when the blower does its magic). I do not know what's going on here, so not sure what this will require, if anything.
I'm a novice programmer, but I have worked with Atmel stuff before-just not the 68HC11, which is what this PCM uses. (two of them, actually) I will provide as much data/testing as I can, and if needed I can send a socketed PCM and harness plugs and wiring pinout. (I've got four here, they're cheap on Ebay!)