I have a problem on a 1994 Honda 2.7 V6 engined Rover 827.
Its emissions exceed the limits. I strongly suspect injector problems but the scope traces didn't look too bad. As a routine I put the scope on the ignition -- although I never really understand what I was looking at -- I never seem to get those nice plots that you see in the library.
Attached is what I see on the ignition. They're so strange that I started another thread using a car that has no fault, to try to understand the waveforms, and the MI074 HT probe.
These traces are from free-running because I had trouble triggering. Due to the slow timebase and limited storage in the cheap scope there is gross aliasing in the display. But now that I have inverted the secondary on Ch2, you can see enough of the ignition event to identify it.
Fig.10 shows three cylinders firing.
Fig.10a is a zoom on the middle event of Fig.10. You can see some of the characteristics. But how to explain the intial dip of Ch2 to about -4.5kV during the current build-up stage of the primary in Ch1?
Fig.10b show the same parade but zoomed out to show the full extent of the "wandering" zero-line of the Ch2.
Apart from the emissions problem the car drives well.
As well as the attachments, the images will shortly be available at:
Grateful for any help,