Originally Posted by libbybapa

I don't know what either of those are. How do they connect? What do they read?

Mine is a standard diesel pulse adapter. It has a piezo sensor that clamps onto the injection line. When the pulse of fuel occurs, the line expands slightly and then is released when the beginning of injection occurs. That slight expansion compresses the piezo crystal slightly and then releases it. That generates a slight current. The pulse adapter translates that slight current into a signal that corresponds to a typical spark signal. A standard gasser inductive timing light then reads the signal and does the typical gasser strobe thing.

http://buy1.snapon.com/catalog/item.asp?store=snapon-store&item_ID=78287&group_ID=1389

It is an easier and more accurate method of timing than mechanical methods, as it measures the actual start of injection automatically "compensating" for pump wear or injector pop pressure.

Andrew