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Unread 07-20-2013, 11:36 AM   #1
JMcDonaldKnives
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1980 CJ7 
 
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Spark problem on 4.2L

My buddies 81 CJ8 with 4.2L is having a problem that puzzle the hell out of me. It only sparks when he first turns the key on and when he turns the key off. New coil and ICM. Its puzzling me. Anyone else ever had this problem?

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Unread 07-20-2013, 12:57 PM   #2
CJuncky
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Sounds like ignition switch to me. Test for voltage at coil with key in on position and start position.

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Unread 07-20-2013, 01:04 PM   #3
JMcDonaldKnives
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I'll have to do that when I get over there
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My Build Threads

1980 CJ7 4.2L T177 D300 D30 AMC20 (under construction)
[url]http://www.jeepforum.com/forum/f8/knifeboy-jeep-build-thread-1387906/[/url]
1989 YJ 4.2L T177 NP231 D30 D35 Pro Comp 3" lift 32/1150/15 BFG AT
[url]http://www.jeepforum.com/forum/f12/knifeboy-yj-build-thread-1720362/[/url]
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Unread 07-20-2013, 02:29 PM   #4
james04si
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And it could just be the switch is misaligned and not actually bad. They have slots for the screws and adjust for the right spot for when the key is in different positions.
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Unread 07-20-2013, 05:46 PM   #5
Caish
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I agree sounds like a faulty ignition switch.
Or if it has tilt wheel, the switch is on the column itself and checl the alignment of the switch, they have been known to come loose and slide up or down causing the switch to be mis-aligned.
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Unread 07-20-2013, 06:24 PM   #6
james04si
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Quote:
Originally Posted by Caish View Post
I agree sounds like a faulty ignition switch.
Or if it has tilt wheel, the switch is on the column itself and checl the alignment of the switch, they have been known to come loose and slide up or down causing the switch to be mis-aligned.
The tilt and non tilt columns have the same type adjustable switch.
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Unread 07-29-2013, 05:55 AM   #7
JMcDonaldKnives
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Forgot to reply with what I found. Turned out to be the distributor. The shaft bearings were getting worn and causing it to hit the pickup. Replaced the distributor and it fired right up. Starts even better than it used to.
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My Build Threads

1980 CJ7 4.2L T177 D300 D30 AMC20 (under construction)
[url]http://www.jeepforum.com/forum/f8/knifeboy-jeep-build-thread-1387906/[/url]
1989 YJ 4.2L T177 NP231 D30 D35 Pro Comp 3" lift 32/1150/15 BFG AT
[url]http://www.jeepforum.com/forum/f12/knifeboy-yj-build-thread-1720362/[/url]
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