2006 Fiesta 1.4 TDCI is randomly misfiring and sometimes cutting out. The pending fault code on forscan is p1204 cylinder 4 misfire. I've checked the wiring to the injectors and there's no visible issues nor are there any leaks from the copper washers. This leads me to conclude the injector needs replacing. Has anyone got any help or advice on this job or recommendation on where to get a replacement recon injector from?

Thanks!

Change the fuel filter first and put some injector cleaner in the tank.

According to forscan, p1204 is injector circuit cylinder 4 open/shorted. I interpreted this to mean there is an issue with the injector wiring or injector itself rather than a misfire due to fuel starvation/delivery. I'm going to try swapping two injectors round and see if the fault follows it. It had a new fuel filter a short time ago however it was only a cheap one.

What sort of mileage is the car on? It could be something internal within the injectors that could be failing, does it misfire after going over a pothole for example? I only ask as it could be a loose connection or something knocks against the injector temporarily but is fine when the car is just idling. Perhaps also perform a leak off test to rule out anything injector related.

No potholes etc don't effect it. It can be fine one minute and misfiring and cutting out the next. It can miss at idle too. Car is on 90k miles. I've read the fuel injector solenoids can be problematic on these so something to look at. Hopefully the fault will follow the injector when I swap two around which will narrow it down.

No potholes etc don't effect it. It can be fine one minute and misfiring and cutting out the next. It can miss at idle too. Car is on 90k miles. I've read the fuel injector solenoids can be problematic on these so something to look at. Hopefully the fault will follow the injector when I swap two around which will narrow it down.

Indeed - perhaps also check things over like the EGR as well just to make sure its not something else that could cause a misfire, I am not sure if our injectors need coding if they are replaced - let us know what you find!

Ok so it turns out it was a knackered injector on cylinder number 4. Or a knackered injector solenoid to be more specific. Rebuilt with a new solenoid and nozzle by swadlincote diesel and it's good as new again. Also to answer above, these injectors don't need coding.