Hi

Normally this vehicle runs well, but on an intermittent basis will run rough and stall with engine check light illuminated and security light flashing. Once it stalls, clicking noises coming from EGR valve and ASD relay, plus fuel pump relay. Also DRB III drops out with “no comms” message and then re-establishes connection. Checked pin 16 and 4/5 on 16 way diagnostic plug, ground seems to go high for a second or so (nothing conclusive). Also engine check light becomes fluttery as if a power failure / ground fault occurs
Following codes are logged but will clear, but once engine starts to run rough and stall, the same codes return. The vehicle will all of a sudden return to running well for no apparent reason.
P1685 invalid skim message
P0351 ignition coil No1 primary circuit
P0352 ignition coil No2 primary circuit
P0353 ignition coil No3 primary circuit
P0202 Injector No2 control circuit
P0203 Injector No3 control circuit
P0204 Injector No4 control circuit
P0205 Injector No5 control circuit
Carried out wiggle test on all looms and fuse boxes, cleaned engine earths.
Checked ignition circuit to ecu (NBV) but not carried out amp draw
Checked ECU grounds and carried out volt drop test to battery ground
Drove the vehicle the other day for 20 miles without a glitch, now its even difficult to start

They say when approaching diagnostics, it is similar to landing an aircraft
You have to approach the runway at the right angle before you get anywhere
With this vehicle I seem to have lost the airfield. Help needed - any advice welcome
Ken Hudson
Ps
Customer does not want to spend any serious money !!!!!