99 xj no spark from coil

I have a 99 xj 4.0
I had the same issue as most people i have read but never found a solution. Upon reading every other post i did alot of testing and replacing.
Replaced the ignition coil,cps,pickup coil, and ecm. Finally got gauges to work on dash. Fuel is kicking on but i cant get a spark out of my ignition coil. Truck will crank all day long but wont fire. Been at it for a few weeks now and running out of ideas.
Any help would be greatly appreciated

Somewhere on this site is a no start checklist that runs through all the possible symptoms. Since you aren't getting spark from the coil, you are already over half way there. At least you know the problem.

Do you by chance know where it is. Im new to this forum just signed up today cause of all the helpful info i have received

You need to start tracing wires from the coil until you find a frayed sheath, loose ground, cut wire or any anomaly. If you can do continuity checks, that would be your best bet.

Ya i found some frays by the grounds right next to coil fixed that all up and still nothin. Am i supposed to have continuous power going to the coil plug?

Why did you start replacing stuff ? What was the original symptoms and problem ?

Typically, a short circuit in any of the wires to the 5 volt OBD-II engine sensors will shutdown the PCM. You will likely need to undertake a systematic and logical physical/visual inspection and electrical testing of the under hood wire harnesses to locate any chafed/melted wire insulation, corroded/damaged wire plugs, or failed wire splices.

You should also test the OBD engine sensors. If you are replacing engine sensors be sure to only buy genuine Jeep parts. Most auto parts stores sell cheap crappy Chinese "Lifetime Warranty" parts that are poorly manufactured and are often out of specification, or even failed, right out of the box. The ones that aren’t faulty often have a short service life before they fail. Always buy top quality replacement parts and genuine Jeep sensors. Numerous threads detail long and frustrating searches for a "problem" that ended up being cured simply with genuine Jeep repair parts.

Cheap parts are cheap for a reason.

Problems with remote keyless entry module and module wiring can also cause the symptoms described.

Original symptoms were the fuel and battery gauge not working. The jeep originally was in a wreck on drivers front and smashed the computer i had it rigged to work and it finally gave out after 2 years. So to start bought a comp and replaced it gauges came on and read up on everythin said cps so replaced that still no dpark so just did the coil...
Just been trying to go off of what everyone has been through.
Been testing wires and searching through. Hooked up scanner today and pulled a code P0320 found some messed up wires repaired them and still having same issue with vehicle thought was a faulty cps so went and exchanged and same problem

Just a thought, but where did the ECM come from? I'm not sure if it applies in this situation, but if you bought one from Auto Zone or the like, most of the ECM's don't come "programmed" or "flashed"....
I only bring this up since I work at one and see it a lot.

I bought it from junkyard out of a 99 same years and same number s couldnt see paying the price for one thats reman or new and not being the problem

Genuine Jeep CPS or some crappy Chinese copy ?

The fuel and battery gauge not working are the common symptoms for a failed or damaged Crankshaft Position Sensor. They can also be symptoms of a short circuit somewhere in the 5 volts OBD-II engine sensor bus circuit.

brandon05990 said:

Original symptoms were the fuel and battery gauge not working. The jeep originally was in a wreck on drivers front and smashed the computer .......

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Due to the pervious crash, I would suspect wire harness / wire plug issues, OBD engine sensor issues, or a faulty PCM, in that order.

It was a genuine pcm factory out of another. The crash wasnt that hard of a crash just enough to crash the fender a lil bit but damaged the plug which i replaced n thats the only damage but i guess all i can do is start following wires like crazy or replace the harmess

brandon05990 said:

Do you by chance know where it is. Im new to this forum just signed up today cause of all the helpful info i have received

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Unfortunately not... I stumbled across it one day. You can search the threads at the top.

I changed the engine harness out and it fired right up