when left to idle it misfires. the misfire gradually gets worse until you can feel the whole car shaking. it feels like theres the occasional misfire at around 2k rpm using light throttle.
the fault code that comes up is lambda malfunction type 2.
the parts that have been replaced are :
idle control valve
MAP sensor
throttle positioning sensor
green coolant temp sensor
lambda sensor (also tested, getting 12v from heater element)
coil packs
spark plugs
fuel pressure regulator
ive also unplugged the injectors one by one to see if the problem stayed the same while replicating the fault, no joy.
there are no vacuum leaks, tested at idle and at 3k rpm by spraying brake cleaner all around the inlet side and connected hoses.
any ideas on what to try next?