Hacking/tuning the jeep ecm

[1project2many]

Thats why I am willing to pay someone to do it.

You probably do not make enough to pay someone to do this work. It takes a lot of time.

Still learning. What is ment by functions?

Math. Mopar systems used math equations instead of lookup tables in some areas. You would need to edit the equation instead of tables full of data.

[shelgame]

You probably do not make enough to pay someone to do this work. It takes a lot of time.


Math. Mopar systems used math equations instead of lookup tables in some areas. You would need to edit the equation instead of tables full of data.

I think he meant the 2D tables. Chrysler used a unique format for the 2D lookup tables. Instead of just putting in X,Y coordinates and using straight interpolation (which must calculate the slope to complete the interpolation); they actually simply encoded the pre-calculated slope into the table. Takes up twice as much storage, but probably only a tenth of the computation time. They started using that format back in '84 in the very first ECU which used a 6805(?) processor that had no divide instruction built in. So, the interpolation would have tken even longer to complete. It was just much easier to give up a little data space to save that precious computation time. Pretty ingenious if you ask me. Since it was a unique format to Chrysler, they kept it even when they went to the more powerfull 6811 (which actually can do division pretty easily).

Because they encoded the slope, TunerPro cannot fully recalculate the 2D tables when a point is moved. TunerPro isn't setup to do the slope. The only programs that do it are D-Cal, CHeM, and the newer MP Tuner.

For what it's worth, I have completely dis-assembled the turbo code back to my own source code that can compile a brand spakin' new binary.

[JeepsAndGuns]

So, basicly your saying tunerpro is not gonna work with the jeep bin files?

My jeep is a 93 wrangler 4.0L 5 speed. The spare ecm I have is actually from a 93 cherokee 4.0L auto. I dont mind opening its and removing the eprom, I just cant do that to one in my wrangler, cause I still need to drive it.
If you have experance with these, do you happen to know the diffrence between auto and manual bins? I had originally bought the cherokee ecm because I red online that they were supposed to have a "better" timing curve to them. I swapped it in and everything ran the same, the only thing I noticed was I actually lost a little torque. So I put my original back in. Would be curious to know the diffrences in the two.
But as I stated before, its all way over my head. I am at the mercy of smarter people who can hack it and get it to the point I can load it into a user friendly tunings sowfware where I can then make desired changes and burn back to a chip.

[shelgame]

So, basicly your saying tunerpro is not gonna work with the jeep bin files?

My jeep is a 93 wrangler 4.0L 5 speed. The spare ecm I have is actually from a 93 cherokee 4.0L auto. I dont mind opening its and removing the eprom, I just cant do that to one in my wrangler, cause I still need to drive it.
If you have experance with these, do you happen to know the diffrence between auto and manual bins? I had originally bought the cherokee ecm because I red online that they were supposed to have a "better" timing curve to them. I swapped it in and everything ran the same, the only thing I noticed was I actually lost a little torque. So I put my original back in. Would be curious to know the diffrences in the two.
But as I stated before, its all way over my head. I am at the mercy of smarter people who can hack it and get it to the point I can load it into a user friendly tunings sowfware where I can then make desired changes and burn back to a chip.

Uusally, the only difference between manual and auto is in the idle control. But, it's possible that the auto trans cal has a bit more timing in places. Though, not likely overall...

[JeepsAndGuns]

I guess the only way to really tell would be to actually compare the bin files. If I could get this cherokee auto trans ecm and bin file defined and tuneable, then I would purchase another wrangler manual ecm to take apart and get the chip/bin out of it so it could be hacked/defined.

[ssmacwilliams]

Have you gotten any further on your jeep obd1 project? I have a 95 wrangler 6 cyl auto,and am looking into doing the same thing. I would like to output everything out to my android tablet, but I am coming up empty as well... I have done a little development of apps for the android and have the IDE to do it, but I am running into the same problem you are. Of course it looks you like you are heads and sholders beyond my full grasp of the project... I did find something that my aide in the communicaiton between a tablet and the jeep. This guy is using bluetooth to connect to a honda.http://www.linszter.net/?lang=en http://www.linszter.net/2011/08/09/t...amhoz/?lang=en But I believe the crux of the matter is the what you have already denoted and that is the "bin" files. I am work with databases on a daily basis and quite often I have to compare 2 database to find modifications that were done. I use some free software called Schema Compare or something like that... I am not sure it will work on a bin file, but it would hurt to give it a shot. Please keep me in the loop I would like to be involved in something like this if you are still pursuing it.

[JeepsAndGuns]

I have pretty much all but given up on the stock Jeep ECM. Its a great ecu, tough and durable, but as far as tuning support, there pretty much none. An those who can do it, will not share. This thread acted like it was gonna take off and go somewhere, but ended up smashing into a brick wall.

I have decided to instead, to convert it over to a GM 1227727 ECM. A few little mods to the engine (dist. and alt.), and hooking up the harness and I should be in business. There is way more tuning support for GM ECM's.