Guys just thought id post this warning.
I regularly change all my ignition parts... Spark Plugs every 2 years (genuine only), Caps, leads and rotor arms every 3-4 years. I do very low mileage.
Anyway this time I used Bosch Caps and rotor arms... everything seemed fine until after a long run i started to get a slight misfire at idle and under high load.. i.e. accelerating hard at high speed.
So I knew it had to be one of the parts id changed. I used magnecor leads so knew that these would be fine.
Cut a long story short, Im almost certain the OEM bosch caps are the culprits... If you look closely inside they have chips out of the casting... I checked 6 new caps at my supplier and they were ALL the same.
I have now swapped to the cheaper, but better made, Beru caps and so far seems ok.
This may have been covered before but thought id mention it as ive seen people swapping all sorts of expensive parts to try and solve these minor misfires...
Look at new caps carefully before installing them.
p.s. anyone changing their caps should also change the rubber seals that fit behind the cap... these go hard every few years.