Electrical
Ignition Coil Waveforms
The ignition coil current waveforms can be monitored using a relatively inexpensive scope and current clamp. This technique can be used to diagnose problems with individual coils as well as some spark plug problems. The following PDF shows known-good ignition coil current waveforms as well as what they look like under a few fault conditions (ignition coil open and ignition coil short).
Fuel Pump – Current Waveform
The health of the fuel pump and its operating speed (RPMs) can be rapidly assessed by a quick look of its current waveform. The shape of the current waveform, pump speed and average current draw are good parameters by which to diagnose a failing fuel pump. Details of the procedure and known good fuel pump waveforms are contained in the following PDF file:
Relative Compression Test
The relative compression test monitors starter current (via a current probe and scope) during cranking to get a quick gauge of the compression of each cylinder relative to the other cylinders. This is a quick and easy test which can be used to check for any significant loss of compression in a cylinder. More details, including known good waveforms are in the following PDF file:
DIY (Do-It-Yourself) Accord Repairs 