I have struggled with an intermittent injector fault on my 1.5DCi (J11a 2017) for the last few thousand miles. The car was OK 95% of the time then clattering and loss of power occasionally but when cooled OK again. Breakdown recovery to home at the start of the problem and was told I had a no 4 injector fault. As it cleared up I left it for a while but it got gradually worse. So tried all the usual tricks, drive hard, use Shell Supermax, add injector cleaner. Nothing really solved the problem so bit the bullet and bought a new injector. Bought on line from PF Jones in Manchester, excellent next day service and OEM injector for £189. As they are coded I also bought an ICarsoft JP V2.0 (£139) that reads all Nissan codes not just those a cheap bluetooth reader picks up, and the device also codes injectors to the ECU and is supposed to retract the rear brakes to allow a pad change (haven't tried that yet). I also have a Mazda MX-5 and it does similar for this car too, just picked up a faulty ignition solenoid that my cheap reader didn't.
The injector change took about an hour to complete, reasonably straightforward for the amateur mechanic and the coding was easy. The car is now running smoothly and has done for the last 6 weeks since I did the job. Decided last week that as a preventative measure, it was probably worth cleaning the EGR valve, so bought some Wynns EGR cleaner, watched the attached video, don't speak the lingo but the vid was extremely helpful (
https://www.youtube.com/watch?v=ZhZr937yYBE). Today I removed the EGR (about 20 mins work), this is what my EGR looked like before cleaning
Most of the carbon was very soft and came away easily, I did have to use a small screwdriver to remove harder bits then attacked it with the Wynns cleaner. This is the result of 30 mins work cleaning it.
A really simple job compared to most EGRs I guess so I think I will add this to my maintenance schedule and do it every third service from now on. I hope this is helpful to other.
