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ECU not connecting while O2 sensor is connected

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A bit of background; I had a dyno tune on which I was told that the CAN lambda module isn't producing any data and my mistake was that I did not twist the CAN wires. The dyno tune was although done using the lambda on the dyno.

Now, I corrected my mistake, twisted the wires using the screwdriver technique, soldered a 120 ohm resistor to the end of the trunk, about 2 cm behind the CAN lambda connector. I hooked it up to the CAN1 port on the ECU, as configured by the tuner. However, when I turn on the ignition to power up the ECU I get an error that the software cannot communicate with the ECU (error code NOT_ENOUGH_BYTES), and the car doesn't start.

It gets weirder, if I disconnect the O2 sensor from the CAN lambda module, the ECU connects and I then reconnect O2 sensor and the connection is still up. The car starts, but if I turn off the car and try to start it again, it won't start until I disconnect the O2 sensor. I attempted to scan for CAN devices but the software was unable to find any.

I verified that the CAN module gets 12v, the O2 sensor gets about 7 or so volts.

It's a Link G4X ECU.

Does this sound familiar to anyone? Busted O2 sensor or maybe just a configuration error?

Sounds like you have a wiring issue and the sensor heater noise is going through the USB or something. Does the laptop connect if you disconnect the 12V supply from the lambda?

How long ago was the ecu purchased? Is it a Plug-in or wire-in ecu?

The moment I read "noise" in your post I came to think of the fact that when I initially set this up I tapped the 12v power from the boost solenoid as a temporary solution (as I was in a pickle at the time), which I suspected was going to cause some kind of noise/interference, but I was told otherwise. Little did I know that this could be the result.

Lo and behold, I changed the power source to a clean, completely separate source and everything is working as intended, the ECU is reading from the O2 sensor.

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