'81 tachometer losing signal?
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From: Deep in the Pisgah National Forest
'81 tachometer losing signal?
I've been working on an inconsistent ignition issue for quite a while and finally solved it earlier today. Ignition wire routing. I drove the car for about an hour and it performed very good if not great. The only issue was that I noticed that the tach would move around a bit, maybe 100-200 rpms.
Figuring the connector at the dizzy was loose or dirty, after the engine cooled down I disconnected the tach wire, removed the metal connector from the plastic holder and cleaned it carefully using a dremel on low speed with a wire brush. Brightened it right up. Then I used a pick tool to tighten the connector up a bit. Finally I cleaned it with aerosol electrical connector cleaner, and reassembled it. Seems to be making good solid contact.
I drove the car after that and now this is happening:
The "blips" are accompanied by a slight loss of power.
Any clue what is going on? The dizzy is a Duralast with a lifetime warranty, installed two weeks ago.
Maybe I should do the same with the ignition wire connector?
Figuring the connector at the dizzy was loose or dirty, after the engine cooled down I disconnected the tach wire, removed the metal connector from the plastic holder and cleaned it carefully using a dremel on low speed with a wire brush. Brightened it right up. Then I used a pick tool to tighten the connector up a bit. Finally I cleaned it with aerosol electrical connector cleaner, and reassembled it. Seems to be making good solid contact.
I drove the car after that and now this is happening:
The "blips" are accompanied by a slight loss of power.
Any clue what is going on? The dizzy is a Duralast with a lifetime warranty, installed two weeks ago.
Maybe I should do the same with the ignition wire connector?
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Thread Starter
Race Director
Joined: Oct 2019
Posts: 10,735
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From: Deep in the Pisgah National Forest
I just cleaned and tightened the ignition wire to the dizzy but it won't stop raining for me to drive it and see if that fixed the problem.
Last edited by Yadkin; Jun 18, 2020 at 01:44 PM. Reason: sp
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Thread Starter
Race Director
Joined: Oct 2019
Posts: 10,735
Likes: 63
From: Deep in the Pisgah National Forest
Thread Starter
Race Director
Joined: Oct 2019
Posts: 10,735
Likes: 63
From: Deep in the Pisgah National Forest
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From: Virginia
Does your new distributor retain the 7-pin ICM (shown in @Big2Bird's post above)? If you've removed the computer, swapped to an older Q-Jet and HEI distributor, you'll need the 4-pin ICM, AC Delco part D1906.
The AC Delco website is great for finding the correct part numbers for your car, which you can then use to search for modern reproduced equivalents.
https://parts-catalog.acdelco.com/ca...log_search.php
Either way, about $30- at RockAuto. Keep one in the car!
The AC Delco website is great for finding the correct part numbers for your car, which you can then use to search for modern reproduced equivalents.
https://parts-catalog.acdelco.com/ca...log_search.php
Either way, about $30- at RockAuto. Keep one in the car!
Last edited by Bikespace; Jun 18, 2020 at 09:24 PM.
Thread Starter
Race Director
Joined: Oct 2019
Posts: 10,735
Likes: 63
From: Deep in the Pisgah National Forest
Does your new distributor retain the 7-pin ICM (shown in @Big2Bird's post above)? If you've removed the computer, swapped to an older Q-Jet and HEI distributor, you'll need the 4-pin ICM, AC Delco part D1906.
The AC Delco website is great for finding the correct part numbers for your car, which you can then use to search for modern reproduced equivalents.
https://parts-catalog.acdelco.com/ca...log_search.php
Either way, about $30- at RockAuto. Keep one in the car!
The AC Delco website is great for finding the correct part numbers for your car, which you can then use to search for modern reproduced equivalents.
https://parts-catalog.acdelco.com/ca...log_search.php
Either way, about $30- at RockAuto. Keep one in the car!