Hi Everybody,
The question, I have is. One of my workmates was faced with the following problem. A JCB dieselmax 444 engine with a runnning fault and starting issue when engine was upto working temperature.The fault was diagnosed to one of the four injectors but which one ? They operate on 70volts. Would the 4 channel automotive scope have picked up the defected injector easily ? Hope this is in the right section.
Cheers, med.
I suspect the fault could have been seen by comparing either the voltage or current waveforms to see which injector looks different. Personally I would use a current clamp as by monitoring the feed to the injectors (eg at fuse box) you can see all the injector waveforms at the same time.
Some faults however may not change the waveform - eg an injector with a blockage where the pintle moves normally may not be detectable with a scope. For this sort of issue, use PicoDiagnostics and the cylinder balance / misfire detect option.
Hi Med, I will be looking into this very issue in an ongoing case study where we are going to evaluate the effect on common rail fuel pressure in relation to injector operation. I hope this will reveal another avenue to assist with injector diagnosis.