Hey all, recently got a p2270 code (see pic) and I'm wondering if this is more likely a dodgy sensor or something much worse like the timing chain? The cars just passed 150000 miles and I have no clue if the timing chains been replaced as when i bought the car four to five years ago the garage...

Got a check engine light, plugged in to OBD, got 4 different codes all pointing to the upstream O2 Lambda sensor. Found a good source of info on how to take 443 pcs off to access the sensor, but nothing on how to get the connector apart that plugs the sensor cable into the computer harness...