Multiecuscan

It would be good, as a marker and indicator, if a line was plotted on a graph when a fault code appears on the system during data monitoring. This would distinguish exactly when an error / fault has occurred and pinpoint what was happening at that time with other signals. Possible?

Good idea and certainly possible.

What I don't know is the ability and latency involved to scan for errors/fault codes whilst doing real time signal monitoring.

If I were doing this then I would be looking for fault codes as a minor issue but certainly focussing on trying to detect the EML signal.

Only Yani or someone else with detailed experience of ECU data reading can reply in any detail.