Good evening people, just after a little help and direction with this.
Set a code P2097 Post Catalyst Fuel Trim System Too Rich.
First image Probing the downstream (red trace) shows 889mv obviously rich.
Blue trace is Pre cat sensor. Not switching.But way too high at 2.74v ??
Second image shows where i have introduced an air leak so this proves (or doesnt it) that this sensor is working. Which turns my attention back to the pre cat.
Not being too familiar with the system, and quite new to scoping im questioning my technique and wondering if for some reason the pre cat sensor is possibly a wideband one althought it only has four wires. Can you get 4 wire wideband sensors ? i didnt think you could.
Is the pre cat fractured or shorted inside ? Just after a bit of info before i go ordering a £200 sensor.
Short term fuel trim is 0.00
Long term fuel trim is 12.50 and neither of them change.
Thanks for any help and input