Technical Fault codes - any single cause?.

[alfacool]

Hi all.
The sei has ran a bit strange this week?.
Seeming to chug and hold back, revs staying high when changing gear and bogging down when stopping and sometimes pulling away.
The EML flashed on a few times, but went out on restart.
Any how plugged my generic code reader in and for a change it actually let me read the codes.
PO300
Random/multiple cylinder misfire detected.
PO135
O2 Sensor heater circuit bank 1 sensor 1
PO340
Camshaft position sensor A circuit bank 1 or single sensor.
PO141
O2 sensor heater circuit bank 1 sensor 2

I have already in the past year changed
Cam sensor.
Coil packs
Plug leads
Throttle body
Top o2 sensor
Checked both oil and water and they are fine, cleared the codes and i will see how it goes.
But could it be 1 thing that puts up all these errors?

 

[rallycinq]

Check your earth connections

D

 

[alfacool]

Thanks David.
You got the locations ?.
Both inner wings then where?