OK got my scope out this morning and the cps is producing a signal. so that should be working at this time.
ok - now swap the rotor and see what happens
If he doesnât have spark from the center coil wire to ground when turning the engine over, a rotor replacement is not going to fix the no start problem.
Tosh: Do you have spark when pulling the coil wire from the center of the distributor cap and holding the end close to ground on the engine when turning the engine over?
I checked ]both with a spark tester and the method you recommend no spark from the coil.
Do you have power at the coil? At the small wire terminals on the low voltage side of the coil
I have power at both sides sides of the coil with the key on.
That is on the low voltage side, sorry i got interrupted when i was replying earlier.
If you hook a separate wire to the ground or negative side of the coil and then make and break the other end of that wire to a ground point on the engine while holding the center coil wire near a ground point on the engine, do you get a spark from the center coil wire when 12V positive from the rest of the ignition supply is supplied to the positive side of the coil?
I will check that tomorrow and report back.
Ok i checked that this morning key on, making and breaking the ground. no spark from the coil.
So you definitely had 12v at the positive post of the coil?
If you did then I would say that you have a bad coil.
A replacement coil on rockauto.com made by Standard Motor products is $57.79 plus shipping or a Bosch coil for $58.79 plus shipping.
Yes I have 12 volts on the power side. I even disconnected the wire from the negative side wire checked on that post. oddly with no wire on that terminal it still has 12v on the post.
Just so I am correctly understanding, can you describe or post a photo of how you were making & breaking ground on the negative side of the coil for this test? Did you do that with a separate wire that you used just for this test as opposed to the original wire that is part of the XJ40 harness?
So the post that i have circled there i was making and braking the ground with a separate wire lead. That post with nothing attached to it has 12v on it.
OK, I understand. I would again say that if you were making and breaking ground with that separate wire while having the coil wire plugged into the center post of the coil and still getting no spark from the other end of the coil wire (held near good ground point on the engine) when making and breaking the ground connection, I would try swapping out the coil for another one. Then retest.
Alright I will get a new coil coming and report back.
Ok so i replaced the coil with the same results. i did learn somethings though, when removing the positive side of the coil I found a broken wire coming off of it. I was looking over the wiring diagram and on that side side of the coil there are 2 wires that is supposed to be going to it. white and pink coming from the amplifier and then the second one they do not give a color to. The second is the one I believe to be broken in the diagram that wire goes through a capacitor straight to ground. This throws me off a bit, but my biggest problem is not being able to able to find said capacitor. Are you familiar on these cars with there being a capacitor on that wire?
Yes, there is a capacitor there. The body of the capacitor bolts to one of the mounts for the coil.
Itâs dark outside here or I could snap a photo of this for you. If you like I can do that tomorrow.
That capacitor being present or not should not keep the car from starting.
So you installed the new coil and when performing the same âmake & break the ground connectionâ test you still are getting no spark from the coil wire?
Yes installed a new coil and preforming the make it break it test still no till no spark. if you could snap a picture tomorrow that would be great. Thank you for all of the help!
I think that capacitor is used as an interference suppresor to stop the radio making a buzzing
noise when the engine is running.
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