My daughter has a 2002 Fiesta 1.25 Zetec SE and it's misfiring on No2 pot. The car drives ok but shudders when on tickover. I have changed the coil, leads and plugs (all new) but it's the same .....HELP if you can.

 

This might sound daft but are you sure each lead is connected to the relevant plug correctly? I serviced my car last weekend and afterwards it was firing like a bag of shit, on closer inspection one lead had not been pushed all the way home on to the plug, as soon as i pushed it fully on it ran perfect. Secondly make sure that each plug is actually receiving a spark, start the engine and remove each lead (one at a time) from its plug and hold the lead near to a metallic part of the engine and check for a good spark arcing across from the lead to the metalwork. Good luck.

 

coils on these r common to pack up will still run but u will get the problem u r getting

 

i imagine its the later shape fiesta?.if the coil,plugs and leads have been replaced and your confident they are all correctly plugged in the id be looking at injectors,compression and even engine ecu.the way i check injectors at work is to take the rail out of the head with injectors still connected.lean it on the engine,stand back and just put the ignition on so the system primes.run your finger over the injector tips and they should all be dry.if ones damp then thats the one thats leaking.
if thats ok then check compressions and if they are fine you should be checking the wiring from engine ecu to the coil pack for open circuit,short etc.failing that being ok i would say engine ecu is faulty as early new shape fiestas did suffer from water in the connector of ecu and causing them to pack up

hope that info helps

 

injector

 

Done an oil change recentley? If not then do it, use 5/30 oil.

If it were a coil pack problem then you'd be only firing on 2 cylinders, even new coil packs are prone not to work properly if it's a pattern part. But as above only on 2 cylinders.

Also i take it this is a mk5?