DVDBurn I see that your circuit basically generates an output signal that is the sum of the single MAF signals, which will not work. The MAF voltage is interpreted by the ECU as a logarithmic signal and converted according to a 256 byte VQ table stored in the EPROM. The only way to "sum" the MAF signals is with a digital signal processing which simulates the ECU behaviour. I suppose the Selin contains such a microprocessor.