check the engine loom multiplug hasnt come adrift,
its the big plug on the bulk head just behind the inlet plenum,
had this happen on mine and known of a few others its happened on.

also remove the sparkplug cover and check both the wires that go to the coil packs,
these always brake up due to the heat build up under the cover and cause all sorts of running issues,
id replace these as a matter of course.


you should replace all the filters and plugs as a matter of course if you dont know when they were last changed.