fuel injection problem on 1975 v12 jaguar

My name is Justin and I am helping Phil with this car. He has asked me to upload this video with what he has found. Thank you very much for the help.

youtube.com/shorts/i3r2aDM6hXs

Hi Justin,

is that the signal from the 2 Hall sensors to ECU? It should be a rectangular signal but with slow frequency. There is a pull-up resistor in ECU and closed Hall sensor pulls it down to 0.

What about distance of finger to hall sensor board?

I believe I had my scope set on the wrong setting when I did the video as it was set to AC and not DC. Doing the same test in DC I am not getting anything. This is a new scope to me so I am still figuring it out. Is there a good way to test the trigger board from it 4 pin connector?

I have been brought on to sort this out as Phil has become frustrated.

Hi,

well I cannot help with this oscilloscope. You can only measure with board being connected.

You are sure that you have a finger with magnet bilt in? It should create pulses in Hall sensor. Magnetic field goes down by distance. So if distance  of board to this magent in finger is too big, it might not work properly.

Yes the rotor does have a square magnet in the back side of it. It is a very strong magnet as I just checked it. I will get the trigger board closer and see if that makes a difference.

The car was running just fine for several months after we rebuilt the engine. The client took it down the freeway for about 30 minutes and on an up hill climb it started missing cylinder until it stopped completely.

I believe I am correct in having the scope set at DC current when testing?

Can I use the scope to test directly at 4 wire connector at the trigger board?

Hi,

DC or AC does not matter for a real oscilloscope. What do you want to measure on that connector when it is off? No power ? no signals.