My 1985 Jag XJ6 starting running a lil bit rough, and missing the other day. Turned it off it wouldn't start again. Figured out that there was no spark coming out of the coil although we were getting power to the connectors on the coil. Decided to try and bypass coil with wire directly from battery to the coil, and it worked! Car started and I drove it home. Is the coil the source of my problem? Note: coil has external resistor

 

Hi Jashuar85,

I haven't had this problem on a Jaguar, but had the same problem on another car a long, long time ago. Replacing the coil and resistor did it for me.

Be careful the way you have it wired now! Again, I had the same exact issue on a different car and bypassed the external resistor. I believe this may be a ballast resistor to limit current drawn by the coil. When I bypassed mine, it worked great for a couple of days, until my wiring burnt out and nearly set fire to the car!

Just a heads up.

Regards,
Beaky.

 

If you hooked directly to the coil +stud and nut, the problem is likely the ballast resistor. If you hooked to the spade lug on the ballast resistor and the engine ran, then there must be something wrong in the power circuit to the coil.

Cheers,