The engine cuts to limp home mode and the orange engine warning light comes on for no apparent reason - very unwelcome on a motorway.

If I turn the engine off and restart, it fires and runs as normal again, but the orange light stays on for a day or two, and then goes off.

My local mechanic recently changed the injection pump flow control valves, as suggested by Toyota - £185 to them! This worked for a couple of months and then the same problem started to recur every couple of weeks.

Have you come across this before? Any ideas as to the cause and cure, please?