My IS200 (W Reg) has been running rough for a while, misfiring with engine management lights and TRC flashing.
Diagnostics showed misfire across all cylinders so I was told to change the coil packs and duly changed all 6 and that solved it for a short time but then the problem came back. Changed all 6 spark plugs on the advice of another mechanic but still the same problem came back. At first it would run fine to start with and if I was on a smooth run (eg motorway and not stopping regularly) it would run fine but once the engine was warmed up if I got stuck in traffic or pulled off at low rev's then the problem would come back.
I have changed the coil packs again in case I got a duff set but problem is still there and is now there all the time from starting off. It still runs but just not on all cylinders and is eating fuel up.
Further diagnostics show misfire on almost all cylinders again but nothing else.
I have been told it may be the crank shaft sensor which I may order but before spending even more money I wondered if anyone else had any ideas?