1 remove the metal casting bolted to the front face of the engine at front behind the radiator, its held on with two 13mm nuts in recesses, so you need a 13mm socket with a short extender bar. (when removing the casting tip upwards otherwise the nuts will drop below the engine requiring removal of the undersheild)
2 locate the fuel rail, black metal tube running lengthways from just above the alternator towards the battery,
3 locate the four wiring plugs for the fuel injectors located just behind the fuel rail pointing diagonally down (roughly 4 o clock position)
OK so heres the test by removing one of the plugs with the engine running listen and look for the engine revs dropping or almost dropping out. if it does reconnect the plug and move on to the next, if when removing the plug you get no change then its good odds that the corrosponding coil is blown, dont stop however reconnect and quickly check the rest just to make sure. then turn off engine and change the coil identified. once changed repeat the test all should now give a change.
tip - the plugs are secured with a metal clip which has to be pulled down wards in line with the plug body, they have a tendency to pull out completely and then drop i found it easier to remove all with a small pair of flat pliers, ensure plugs are pushed in and then start car and do tests, once complete refit the clips by removing plug, locate clip but dont push in, keep slight pressure on the clip relocate plug and the push clip in, it will push in and then move back out by a few mm. warning this can be a little fiddly, take a breath and dont get stressed
dropping the clip will almost certainly require removal of bottom engine shields. you can also hedge your bets and not bother with the clip/plug over ther alternator as for some reason i found it more of a pain.4 make sure all plugs are relocated and engine is running now switch off
5 refit the casting there are two cables one slots into recess at each end of casting midway down, the other runs along the top held in locating lugs, also ensure no wires are trapped.
6 take car for a run, at this point i patted myself on the back and won smartie points from the OH.
I spoke to my brother in law who as luck has it owns his own garage, he agrees with the method it is safer cutting the fuel as opposed to removing the coil from the spark plug whilst running as the change in load can blow a serviceable coil. its also not only the megs his work citroen a V6 is doing the same 5 down one to go apparently
Hope this makes sense, would of liked to have taken photos but was in a rush to go on holiday,
