Thanks Carl for your reply,
Carl Grotti wrote:
Why did you use engine cranking current in the second capture instead of using a low current probe on the fuel pump circuit?
This is not a fuel pump but an engine driven oil pump.
What's odd about the first capture is the pressure appears to go to about 100psi at the very instant the engine starts to crank
In this one,I inverted channel A and adjusted the scaling and both siganls are almost identical.Hope this makes my question a bit clearer.
This is really annoying me because I have other saved captures from only a few months ago,using battery volts and the WPS and they are fine.So what has changed?