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I have no spark I've changed the following, ignition coil, rotor, dist cap, magnetic p/u and computer?

Tiny
COPEMAN
  • MEMBER
  • JEEP CJ7
83 jeep cj7 165,000 mi 4.2 engine I have no spark i've changed the following, ignition coil, rotor, dist cap, magnetic p/u, and computer is there any inline fuses or something else i'm missing?
Friday, November 16th, 2007 AT 11:04 AM

15 Replies

Tiny
FISHERMAN
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Hello !
Did you tried to "run" a positive wire from the battery to the ignition coil?
That way you will know for sure that the problem its not the ignition switch or the control wiring.

Let us know!

If the problem persist, tonight, as soon as I get home i`ll send you an a wiring schematic on your ignition system.

Good Luck!
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Friday, November 16th, 2007 AT 11:29 AM
Tiny
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Hello Copeman.

Disconnect the positive wire from the coil and connect there the one from the batt. (+)

leave the (-) side on the coil. Thats the one it came from the pick-up coil and igniter

that way you will know if the ignition switch its good or not (process of elimination)

good luck and let me know any other question.

I`ll post this on your thread.

(copy and paste from my PM)
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Friday, November 16th, 2007 AT 5:13 PM
Tiny
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Hello Copeman!!

Following your question here its the schematic of your Jeep:


http://www.2carpros.com/forum/automotive_pictures/576_Jeep_1.jpg



Leave the Capacitor and the (-) (from the ignition module) connected.... just disconnect the red wire and connect an straight wire to the positive terminal of your battery..
that way we will find if the solenoid and your ignition switch are good or not..

let us know on this thread..

Good Luck!!
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Friday, November 16th, 2007 AT 8:31 PM
Tiny
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Fisherman,
I don't think the problem is an ignition switch because it turns over strong, and I have spark at the top of the coil but not at the plugs.
Thanks
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Friday, November 16th, 2007 AT 8:35 PM
Tiny
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OK. I though you have no spark at all, then the spark out of the coil. Its constant I mean "click click clik" when cranking?
If you connect a tester light on negative of the coil and the other end on the positive (of the coil) did you get "pulses" (on-off-on-off?

Let me know.
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Friday, November 16th, 2007 AT 8:42 PM
Tiny
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OK. I though you have no spark at all, then the spark out of the coil. Its constant I mean "click click clik" when cranking?
If you connect a tester light on negative of the coil and the other end on the positive (of the coil) did you get "pulses" (on-off-on-off?

Let me know.[/Quote]

Fisherman,

I tested the coil and yes I get pulses on and off
and then I tested for spark again @ the plug and nothing. What do you suggest next?
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Monday, November 19th, 2007 AT 11:08 AM
Tiny
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Fisherman,

I tested the coil and yes I get pulses on and off
and then I tested for spark again @ the plug and nothing. What do you suggest next?[/Quote]

Hello !

Which plug you`re testing for spark?
An spark plug or the wire that "feeds" the distributor cap?

Well.

Check for spark directly on the coil output.

(the wire that goes to the distributor cap)

sometimes the coil is defective (even new) I saw some cases like that.

If the spark its good there the problem should be the distributor cap or rotor (the spark its missing inside due to a "moved" rotor in respect the cap post when the coil its sending the spark)

the cap could be out of place.

But the problem its there. Right there!

Good luck and let me know!
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Monday, November 19th, 2007 AT 11:44 AM
Tiny
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Hello !

Which plug you`re testing for spark?
An spark plug or the wire that "feeds" the distributor cap?

Well.

Check for spark directly on the coil output.

(the wire that goes to the distributor cap)

sometimes the coil is defective (even new) I saw some cases like that.

If the spark its good there the problem should be the distributor cap or rotor (the spark its missing inside due to a "moved" rotor in respect the cap post when the coil its sending the spark)

the cap could be out of place.

But the problem its there. Right there!

Good luck and let me know![/Quote

fisherman,

ok I checked the spark @ the coil lead it's good,
i checked the cap and rotor they also look good
but no spark on the wire at the plug.
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Monday, November 19th, 2007 AT 1:46 PM
Tiny
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Quote fisherman,

ok I checked the spark @ the coil lead it's good,
i checked the cap and rotor they also look good
but no spark on the wire at the plug. Quote

OK

how are you checking the spark?
With a screwdriver or with a spark plug?

Its the wire good?

Did you check all of the wires?

Its the cap and rotor right in place?

Did you move the distributor out of time?

Let me know on that!
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Monday, November 19th, 2007 AT 2:09 PM
Tiny
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Fisherman,

i checked the spark with a screwdriver and with a test light, the wires are all new and I put the rotor and the dist. Cap on the same way it came off.
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Monday, November 19th, 2007 AT 2:34 PM
Tiny
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OK

The spark its "missing" somewhere in between the coil and the spark plug.
You said that you replace the pick-up coil. It is well align?
I mean exactly the way it should?

My point is: the p/u coil "send" the signal to the coil, the coil send the spark to the center of the distributor cap, then that spark its transfered to the rotor and the rotor send it to the distributor cap post and from the post to the spark plug
If the rotor send the spark and the post its not close enough. The spark disappear!

Something its wrong here.

Using the common sense the pick up coil its not sending the signal on time (you said the "timing" has not been moved)

check that and let me know.
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Monday, November 19th, 2007 AT 2:55 PM
Tiny
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OK

The spark its "missing" somewhere in between the coil and the spark plug.
You said that you replace the pick-up coil. It is well align?
I mean exactly the way it should?

My point is: the p/u coil "send" the signal to the coil, the coil send the spark to the center of the distributor cap, then that spark its transfered to the rotor and the rotor send it to the distributor cap post and from the post to the spark plug
If the rotor send the spark and the post its not close enough. The spark disappear!

Something its wrong here.

Using the common sense the pick up coil its not sending the signal on time (you said the "timing" has not been moved)

check that and let me know.[/Quote]

Fisherman,

Ok I went back into the cap I found when I changed the p/u that I had gotten the rotor assembly 180 out, no problem I put it back and guess what? Nothing still no spark I think i'm going to have to have it fixed by a pro.
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Tuesday, November 20th, 2007 AT 3:41 PM
Tiny
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Fisherman,

Ok I went back into the cap I found when I changed the p/u that I had gotten the rotor assembly 180 out, no problem I put it back and guess what? Nothing still no spark I think i'm going to have to have it fixed by a pro.[/Quote]

Hello !
Well.
Last try.
Move the "timing" (I mean Move the distributor one side. ) MARK THE ORIGINAL POSITION FIRST!

Meanwhile check for spark.

Where do you live?

(its really hard for me to give-up)

Good Luck!
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Tuesday, November 20th, 2007 AT 4:04 PM
Tiny
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Is the mitchell manual good for me to have?
How much is it?
I saw on the site that it starts @ $9.99 is it a monthly payment.
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Tuesday, November 20th, 2007 AT 5:44 PM
Tiny
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Where do you live?

(its really hard for me to give-up)

Good Luck![/Quote]

Fisherman,
did you get my last message?
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Tuesday, November 20th, 2007 AT 9:11 PM

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