For code 42 does ur speedo work if not then the speedo cable coming form the transmission is broken. so the speedo sensor is not getting a signal. If it does work then the speed sensor is bad. I don't know if that is causing that problem or not. Now for the code 11 check the main grounds for the ecu. they r 2 brown and 2 white wires that r bolted to the intake right above the starter. Just try cleaning them first and erase the code to see if it comes back again later.
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