Cylinder 3 and 4 have no spark

I have had this problem about a month on my 2000 Jeep Cherokee with the 4.0. Cylinder 3 and 4 have no spark. i have changed the coil, ecm, camshaft position sensor, crankshaft position sensor, and the plugs on those cylinders. I have tested the continuity between of the wires from the ecm to the coil and everything is good. I have done a compression test and both cylinders read 160 psi. It is throwing codes p0300, p0353, p0304, p0303, and before changing the ecm it wouldn't go over 3000 rpm. If any one knows what it could be please help.

Possible cross-firing. A little long but.........
https://naxja.org/forum/showthread.php?t=1145993

Could it need one of those coil pigtails that swap the wires around?

That only applies to a Viper coil swap.

Since cylinders 3 and 4 share so much in common.......
Is it possible that you switched the fuel injector plugs?
Have you pulled and read the spark plugs?
Have you checked the manifold vacumm?
Have you checked for intake manifold leaks?

Also swap injectors 1 and 3, and also 4 and 6 to see if the codes moved.

I've never moved the injectors. Can bad injectors cause a coil to have no spark.

its not anything to do with the manifold vacuum or leaks unless that could make the coil not fire at all.

Could it be a bad coil on the new coil pack?

The codes are just saying it isn't firing "properly", not no spark at all.

What brand and type of spark plugs ?

Genuine Jeep replacement parts, or cheap crappy Chinese clone parts with a Lifetime Warranty ?

I would follow the trouble codes for where to begin diagnostics and troubleshooting. Cheap crappy Chinese parts are cheap for a reason.



P0353 JEEP - Ignition Coil 3 Circuit


Possible causes
•Faulty Ignition Coil 3
•Ignition Coil 3 harness is open or shorted
•Ignition Coil 3 circuit poor electrical connection
•Faulty Engine Control Module (ECM)


P0303 P0304 JEEP - Cylinder Misfire Fault Detected


Possible causes
•Faulty spark plug 3 or 4
•Clogged or faulty fuel injector 3 or 4
•Faulty ignition coil 3 or 4
•Fuel injector 3 or 4 harness is open or shorted
•Fuel injector 3 or 4 circuit poor electrical connection
•Ignition coil 3 or 4 harness is open or shorted
•Ignition coil 3 or 4 circuit poor electrical connection
•Insufficient cylinder 3 or 4 compression
•Incorrect fuel pressure
•Intake air leak

Here's what I get for a P0353...
P0353 Ignition Coil # 3 Primary Circuit Peak primary circuit current not achieved with maximum dwell time.

Josephksapp said:

I have had this problem about a month on my 2000 Jeep Cherokee with the 4.0. Cylinder 3 and 4 have no spark. i have changed the coil, ecm, camshaft position sensor, crankshaft position sensor, and the plugs on those cylinders. I have tested the continuity between of the wires from the ecm to the coil and everything is good. I have done a compression test and both cylinders read 160 psi. It is throwing codes p0300, p0353, p0304, p0303, and before changing the ecm it wouldn't go over 3000 rpm. If any one knows what it could be please help.

Click to expand...

Light it on fire and roll it down the hill