Service and faults

Hi Guys, a bit of help needed please.
My TD5 went in for 222,000km service this week. Asked them to look at slight vibration at 120kph. Reported back that all drive train and suspension bushes etc was ok but suspected engine related misfire causing the vibration. Reported faults via the test book.
1). No 1,2 5 injectors - open circuit
2). No 4 injector overfuelling
3). Cruise control stuck

I will replace the No 4 injector with a re-conditioned one but what does open circuit mean and would this cause slight misfire / rough idling??

Sometimes the cruise control doesn't work but resets itself when I start the engine again - This is very infrequent and doesn't really bother me. I assume that is why a fault code has been stored.

The open circuit faults are probably caused by oil in the injector loom - thats simple enough - do a search on here for that.
The overfuelling fault bothers me,I dont recall ever seeing a fault worded like that.A sticking nozzle would cause it - and quickly chew a hole in the top of the piston.Did it actually log that code or did they see large negative compensation values on live cylinder balancing ?

Hi eightinavee,
I gather they saw negative compensation values in the live cylinder balancing.....whatever that means

It means the engine ecu is trying to cut down the fuelling on that cylinder.The ecu looks at the rate of acceleration seen by the crank sensor for each cylinders firing stroke to work out the injector duration.(Can be multiple events per firing)Testbook shows values of + or - 25 on TD5 cylinder balancing.They normally hover around -5 to +5 on a healthy engine so if it consistently more than -15 I'd be looking for a reason.High positive values are normally poor engine condition,piston/ring damage etc.Negative is too much fuel,could be worth swapping injectors around to see if the fault moves - but you would need to rewrite the injector codes into the ecu for it to be a valid test.