One of my newer tools to make my life easier diagnosing engine problems is an in cylinder pressure transducer. Here I have captured a waveform with my new toy/tool using my oscilloscope. This engine cranks over but does not start. I had performed a "regular" compression test and found the the engine seemed OK at around 150psi of pressure, but I heard something a little odd like pressure coming back through the inlet. The crankshaft position sensor on this engines lives behind the timing cover and i couldnt find any wiring diagrams or pinouts for the engine computer so cam/crank correlation waveform was in the too hard pile and was going to take too much time. To make matters worse there was no usual P0016 code as usually found in the engine computer after a scan that would tell me that there is a problem with the valve timing. This is where my new tool comes in where I can simply unscrew a spark plug and see what events are happening inside the engine. This engine cranks but does not start. Looks like ive found your problem lady.
The exhaust valve is opening halfway down the power stroke precisely 50 degrees too early, likewise the intake valve(driven by the same belt) has closed 50 degrees too early and essentially no air/fuel mixture has been pulled into the cylinder to make a combustion.
That sound I could hear was happening right before the 360degree mark where the intake valve is open but the piston is heading in the wrong direction Next step is to tear it apart and rectify the problem.
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