ASD relay in your underhood fuse block. I just replaced mine because it wouldn't start cold. I had the exact same thing no spark and I had replaced the cps and coil. It took me a long time to figure it out. I hope this helps.

 

Ok. After all this, I have no power going to to coil. Checked the primary with key on. I thought my dad checked it and said it did. I switched the ASD relay with another one. Checked all the fuses. Still nada. The CPS wouldnt prevent the coil from getting power to it would it?

Now i know why I'm a plumber and not a mechanic.

 

I'm in the middle of the same issue. I replaced my CPS with an aftermarket unit 3-4 months ago, there was no power to the coil because of the CPS then. It started to fail gradually (rough idle and reduced mpg's) over the course of the last couple of weeks. It gave me a CEL (Check Engine Lamp)and I drew the dreaded "P0340" DTC (Diagnostic Trouble Code) via OBDII a few days ago and then it failed entirely last night - now dead in a parking lot with a CPS bolt dropped inside the tranny housing. Believe it when these guys tell you that the CPS has, umm, crapped the bed - and that an aftermarket CPS cannot be trusted.

 

aftermarket CPS arent the best. I bought one from Autozone and to just get mine running right I had to slot the bolt holes for it to get the right air gap between the sensor and the flywheel. The CPS wont let it fire up if its not sending a signal to the ECM, The ignition switch provides the power to the ASD relay then the relay provides power to the crank and cam sensor then when those 2 provides signals to the ECM the ECM tells the engine when to fire and provide fuel

 

I'm about to pull my hair out here. I have power to the coil, injectors, fuel pump, and CPM when the key is first turned on. I have power to them when cranking. I have power to the PCM. I have no spark from the coil to the distributor. The coil tested good, but could it still be a bad coil?

 

Wow I"m sorry that the xj is being so troublesome. I found this, maybe it will help:
http://autorepair.about.com/library/faqs/bl077g.htm

 

Well, I decided to just go throw another 35 bucks at it and all this time it was the coil. Started right up. It was an expensive lesson, but I learned tons of other stuff while trying to figure it out.

Thank you to everyone who responded.

BTW: I have an extra Crank Sensor for sale if anyone is interested. I bought and installed one from the dealer after I read about the aftermarket ones. Its a BWD from Oreillys.

 

Glad you got it sorted out.

 

yea mine was doing the same thing. a new CPS fixed it

 

Micah, Go to O'Reilly and get your money back. Bring your receipt from them, the receipt from the dealer and the unused CPS (wiped clean). If you have to fib then tell them you bought the wrong sensor or some plausible excuse like "it was a bad relay" or something (they hear them all the time). I returned my failed CPS to the a/p store where I bought it after using it for 5 months and I got back $106. I told them that their vendor sold unreliable components and made only a little fuss because these things should last about ten years - but I knew to not be nasty about it else they would have told me to go take a flying s#*t for myself. They wanted to make a copy of the receipt from my recent purchase at the dealership so I obliged. That was easy!