I've done everything right : ground the green connecter and put my car to on.

Check engine light goes OFF, then ON buts stays ON instead of giving codes.

I want to check my codes because somedy took my ECU and pressure sensor and tried it in a malfonctionning car. Wiring was messed up near ECU. Now when I drive my car, I put a little bit of throttle and the check engine open and stays ON and I can't put power, like the limp mode. I stop it and try it again. Same thing, the check engine light appears when I put throttle. The "malfonctioning" car was doing the same thing.

Changed the pressure sensor without any effect.

Now, I would only be able to check my codes, but my guts thinks that the ECU was "messed up" with the bad wiring of the other car... could it be possible ?

Anyway, I just want to know why can't I check my damn codes...

Thanks