I have been wondering why is there not an ECU out for the American ISx50? I have just been reading about how hard it is to program for this car. Why is it easy to program a ECU for some cars and not for others. I had a Volvo S80T6 before my IS350, and had an ECU on it which took the car from mid 14's to low 13's. I have just been wondering this for a while now and if anyone know a little more about programing ECUs for this car.

 

Because until fairly recently Toyota has not used flash memory in any of their ECMs. They used EPROM onboard the CPU with fusible links so they program it, burn the links, and prevent anyone from accessing their code.

Few outside Toyota have been granted access to TCCS. Lotus have the source code for programming the Elise engines, but outside this, I know of no one given permission to see Toyota's engine management source code.

Add to this the checksum used to identify the code at start up, and the fact no one has successfully cracked the encryption algorithm Toyota use for their ECM code hash. So even if you are able to download the code, you won't be able to make the engine run without the correct checksum.

Obviously, this will change since they've now started using flash memory and it is possible to access the code directly. Still, I haven't heard of anyone succeeding so far. It may be a little while yet.

Also, there is no way you will get an NA car from mid 14's to low 13's with an ECM reprogram. Your Volvo responded to the change because you added boost. So did my Supra. Without added boost, there is no way you'll see the kind of increase necessary to get the car from mid 13's to mid 12's without a lot of other supporting mods and compromising the car's luxury and driveability.