Wont stay running.

So lately when starting my xj it won't stay running until the aruond the 20th time. It turns over and then start but dies as soon as you let go of the key.

New engine last march. just started recently doing this.

Find the ballast resistor, its on the driver side fender. Its a white ceramic block with a bolt through the middle and two orange (I think) wires attached to it. Try bypassing that by connecting the wires together. You can use a paperclip or whatever. If that fixes it, leave it you don't need it. If not, then have an assistant check for voltage on the wires after it starts and see if it drops off at the same time that it dies, thats the power for the fuel pump when the engine is not cranking. If it still has voltage then start looking for at the ignition switch.

Thanks for the help. I will do so tomorrow. This has become a real hassle.