Erratic Spark

[Victor S.]

Ok here is the problem. I have a 91 XJ I6. Have replaced the Crank Position Sensor, Fuel Pump, Distributor, ECM, Cap, Rotor, Plug Wires, Coil,and lastly the wiring harnes under the hood. I have spark from the coil to the cap but not out of the cap. Power to the coil is strong and the ground is erratic. Go to crank it and get a backfire through the exhaust. Out of ideas. Any help is greatly appreaciated for soon it will go to the junkyard if I can't figure this thing out. Thanks for the help Victor S.

 

[McQue]

I would think this problem has to be somehow associated with the distributor...it sounds like you need to go over the mechanical distributor indexing...ie; makes sure everything is lined up right for TDC...spark to the cap but not out of the cap says cap or rotor or distributor is cracked, wrong part, installed wrong , shorted, open or fubar...only other thing I can think of is, if you have one, maybe your igniter( ignition capacitor) is intermittently shorting out...I have only seen this happen once...

 

[Victor S.]

Ran good for about 3 weeks than delevolped a hiccup. started throwing parts on it and it wont run now.

 

[xalexjx]

on the left hand side of the block on the oil dip stick mounting bolts theres three ground wires. Make sure its tight/ clean conection. Sounds like that is your problem.. If not timing chain? Timing off?

I had the same problems when i swapped my engine last spring. The two guys who work for me were just finishing pulling it as i was working on the new engine and they just cut the wires. I finished the swap and couldnt get it to run for a day or two then found that out. was getting power to the coil but no spark.

 

[Victor S.]

Update, all the ground wires to the block, the firewall have been cleaned and tighten. I still have the same problem of spark coming from the coil to the cap is erratic. It will be normal when you go to first start it, than it flashes for a second than pause than flash. That also goes for the groound to the coil. Again any help is appreaciated. Victor

 

[89xj]

distibutor may be 180 degrees off.

 

[8Mud]

I'd say either weak spark. A spark that may be taking odd paths to ground. Or your CPS is getting flaky.

 

[tshumaker]

HI,

Were you able to solve your problem? I have the exact same problems.

 

[souske]

We should hope so, 4 years is a long time to have a car just sitting.

Tschmaker if you can post up the year and your symptoms, there is someone who can help you.