Hello, as above, I have an intermittent misfire.
After a breakdown, cam belt slippage, head repairs, and fingers being pointed in various directions, the immobiliser was bypassed in order to allow me to start the car.
What it now does, with a new set of plugs, is run nice and smooth for about a month, and won't miss even in low revs in higher gears. Then gradually the miss gets worse and the engine note goes nasty again.
It appears that minor aging of the plugs is causing this, but clearly it shouldn't.
Short of getting bled dry by a diagnostics place, which may not provide the answer anyway, does anyone have any ideas as to what could be behind this?