Can the stock ECU be progammed? Is there an aftermarket ECU that can? I’m doing the hypermile thing and am looking at options. The Scanguage probably won’t work on these trucks.
I really believe that with the right equipment and the the right software the factory ROM, read only memory, could be rewritten. The problem is unless you come up with the the equipment and software you are sol. All computer boards should have what is known as a jtag. With this jtag you can read through the whole board to trouble shoot any problems. With this you could also access the memory chips and erase and rewrite the chips. It would take the right software of course to do all of this. To my knowledge this software has not been written, and if it were you would need different software for every make of auto. ( I think ) It will interesting to see if this sort of thing comes out on the internet. Right now you can buy units that can be rewritten useing programs that can be run on a windows laptop. I really think the factory ECU could be rewritten as it is, but there is little profit in this. As far as a jtag, more than likely a plug that is like the one on the car could be used to see all the programs and rewrite then. If you were able to get some computer geeks interested in this it would on the net the next day or so. There only a few things you can change on this computer, but I think in your case you could tweak it for a few more mpg.