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'01 XJ Won't start. New CPS and coil rail, still no spark. Any ideas?

tokarev

NAXJA Forum User
Location
Arizona
Summary:
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I have a 4 door, 2001 Cherokee Sport XJ 4x4 with 145,000 miles that I have been using for a daily driver.
Out of the blue one day, it ran rough then died.
Now it will not start. The engine turns over but won't fire.
I have tried replacing the Crankshaft Position Sensor, the Spark Plugs, and the Ignition Coil Rail. Still nothing.


More Info
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I've been driving it about 70 miles a day. About 2-3 weeks prior to this, I had the transfer case rebuild at a shop, if that's relevant.

On my way home from work, I stopped at a store near my house for less than 5 minutes. When I started it back up, the "Check Engine" light came on, and it ran extremely rough - sputtering and coughing. The motor never smoothed out, and it would not go above 40mph - acted like I had a governor on it or something. I limped it 3 miles home, and it died (luckily) right in my driveway. I coasted it into it's parking spot, and there it's sat for the last 2 weeks.

The engine turns over, but it never fires.

I borrowed a code reader, and here are the codes the Check Engine Light threw:

P0300 - Multiple Cylinder Misfire
P0301 - Cylinder 1 Misfire
P0306 - Cylinder 6 Misfire
P0351 - Ignition Coil 1 Circuit

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First I tried replacing all of my spark plugs with new ones, but that didn't fix it.

After searching this forum, I guessed the problem was my Ignition Coil Rail, so I ordered this new generic one from Amazon and installed it:
https://www.amazon.com/gp/product/B00WMO9IKK/ref=oh_aui_detailpage_o05_s00?ie=UTF8&psc=1

Unfortunately, that new ignition coil rail didn't fix the problem.

So, after some more reading, it seemed the problem could be my Crankshaft Position Sensor. My old one tested OK with a multimeter, and my odometer and gauges were displaying normally, but I didn't know what else it could be, so I bought a new OEM Mopar sensor from the Jeep dealer and replaced my old one.

Unfortunately, that new OEM Crankshaft Position Sensor also did not fix my problem.

So then I tried to see if I was getting a spark from my spark plugs. I pulled my ignition coil, left the spark plugs in it - bottom up - and ran wires from the bottom of each spark plug to ground. I then had someone turn the key while I watched the spark plugs.

I am not getting any spark on any of the spark plugs.

The engine was running fine before it just suddenly quit like that.

Does anyone have any ideas why this isn't getting a spark, before I tow it to an engine repair place?

Thank you in advance for any assistance you can give.
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Does the fuel pump prime for 3-6 seconds when you turn the key ? Have you jumped the fuel pump relay and tested the fuel pressure ? Have you inspected the Camshaft Pickup Sensor assembly ?

Have you read this and checked the Cam Sensor synchronization ? >> http://jeep.blackonyx.net/pdfs/jcss.pdf

Inspect the wire harnesses and wire plugs at and near the transfer case. Look, for loose connection, corrosion in the plugs, damaged or missing pins in the plugs, damaged wires, and chafed wire insulation. Confirm that the O2 sensors are functional and their wire harnesses are not damaged.
 
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UPDATE:

I tried replacing the camshaft sensor, but it still wouldn't start. I was at my wit's end, so I finally gave up and towed my Cherokee to the repair shop.

Two days and $100 later, They told me that my fuel injector fuse had blown when my camshaft sensor went bad. They replaced the fuel injector fuse, and it started right up.
 
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Fuse position number?
 
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