Engine Management And Traction Control Lights Flashing

[Mrs Arnie]

Hi there, I'm hoping someone will be able to assist me with my poorly IS200. She's done just over 146,000 miles and has never let me down in the 6 years I've had her. She's had regular servicing and the normal cambelt/waterpump changes.

The lights starting flasing last week and she was running really rough. We done the normal testing and it showed coil pack 1 and 4 were misfiring - replaced them and plugs at the same time and she was fine for 48 hours and then the same thing happened again.

Got another diagnostic reading from a diagnostic specialist which pointed to the crankshaft sensor - replaced that and also cleaned out the camshaft sensor too as it was a bit dirty, cleared the codes and she was fine for the first 10 miles and then the lights came back on .

Another reading has showed coil pack 1 and 6, but not 4. Read some posts on here which said that it could be the throttle body valve which can get stuck - had that cleaned out today and she ran like a dream again for the first 15 miles and then bingo, the lights came back on and she's misfiring.

Have swapped coil 1 with coil 3 to see what happens, but we are suspecting that coil 1 will come up again just due to the misfiring scenario.

Any other ideas would be grateful appreciated - running out of ideas and just want her fixed.

Thanks