1989 1.6 code 42 -Amplifier control signal, high v - xrictodGRE
how can i fix this problem??
1989 1.6 code 42 -Amplifier control signal, high v - Number_Cruncher
Is this a 16SV engine, and is the code from the MSTS system?

What are the car's symptoms?

1989 1.6 code 42 -Amplifier control signal, high v - xrictodGRE
the engine is c16nz and the ecu is motronic. the symptoms are low power and sometimes engine light flashes in low rpms or remains on after half hour in high rpms
1989 1.6 code 42 -Amplifier control signal, high v - Number_Cruncher
If it's a C16NZ, then it's a Multec single point injection system, not a Motronic.

Check the wiring between the ECU and the DIS unit, and also check the earth wire from the DIS unit. Check also the resistances of the DIS unit, the high tension leads, and the plugs.