Morning all, my names Bill and I work at a garage in South Devon.
I am currently battling with a 2007 Sprinter which came in for reported lack of performance.
Initial scan showed fault codes for DPF pressures sensor, boost air temp and all four injectors shorted to ground but apart from a lack of boost pressure drove ok with no misfires.
Replacing the DPF sensor and air temp sensor restored the lack of boost and all codes cleared.
Smugly went on extended road test with loads of boost until it cut out after 3 miles and had to be towed back.
Fault codes 2123-8 injector output stage 1 and 2503, 4, 5 and 6 for all injectors shorted to ground now present.
Have checked resistance on all injectors, checked loom both with meter and had it all apart too. Injector plugs all good and replaced one which was broken. If injector 4 is disconnected, the one with the broken plug the van starts and runs fine on 3 cylinders but if 4 is reconnected starts and dies. When 4 is disconnected only a code for cylinder 4 occurs - no other codes appear.
When you try to restart with all injectors connected, fuel pressure is slow to build up but with no4 disconnected it rises immediately and starts as normal.
A friend has looked on KTS known fixes and there is a reported fault that the pressure releif valve on the rear of the rail can not hold pressure and cause these codes but I cant understand why the ECU would gives codes for injector shorts for a lack of fuel pressure. Any advice greatfully received. Cheers Bill