I am having issues with the ECM. I keep getting a low mass air flow reading (zero reading). I found that there was something wrong with the oxygen sensors that were shorting the mass air flow input to 4 ohms impedance on the output. After disconnecting the oxygen sensors the impedance was back to a high value which is what I would expect from a digital input. After connecting a different mass sensor, I still get the same reading. Is there a schematic diagram available for the ECM? I think there is an open inside the ECM module. Any other thoughts?