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GWJoe 01-21-2006 06:12 AM

On my 90 GW I am dealing with a no-start that developed after an intermittant no start. I have another post on here about the Mallory Hyfire install - I am waiting on a harness adapter to put that in (didn't feel like hacking up the rig's harness).

In the mean time I am wanting to check the pick up coil. I bought an analyzer to checks resistance (ohms) although it is not digital I think I have figured it out. My question is the specifics of checking the resistance. I am following the Haynes manual instructions and am lacking some info. I have tried checking the wires that plug in across from the orange and purple wires at the harness (can't remember the colors) although the Haynes manual says to check across the purple and orange at the harness (there is not an orange and purple at the harness just the ones that correspond to those on the ICM). Anyway I am not getting any resistance.

Do I do this with key turned on, key off, while trying to start? It doesn't address this in the Haynes manual.

sorry for long post but I want to try to make it clear as I can.


mdill9 01-21-2006 08:24 AM

pull the cap and look at the wires going to the
coil, self expainitory.
The coils do go bad with intermitant open/shots,
are about a $20 part with 20 min to install,
swap it out, see if it helps if not keep the old
one as a spair and swap the ignition module.

Mike D.

Chevelleguy 01-21-2006 11:52 AM

You don't check the resistance at the engine harness, you check it at the harness coming out of the distributor. With the ohm meter hooked up, you also need to move the vacuum advance plate to flex the wires in the dist. this is usually where the problem comes from, broken wires.

[ January 21, 2006, 05:53 PM: Message edited by: Chevelleguy ]

GWJoe 01-22-2006 02:18 AM

thank you guys. My biggest area of weakness in terms of FSJ/automotive-in-general maintenance and repair is electrical, especially ignition stuff. I guess it is time to learn and you guys are all great teachers.

Chevellguy: I would have never thought to check the resistance at the engine harness, but my Haynes manual "explained" it that way. thank you for straightening me out.


Thanks again,


[ January 22, 2006, 08:19 AM: Message edited by: GWJoe ]

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