Mystery plug!

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Jul 6, 2020 | 10:52 PM

L82 crusin

Thread Starter

Intermediate

Joined: Oct 2018

Posts: 39

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Mystery plug!

Hi all!
need some help identifying a mystery plug I found in my engine bay the other day, the car is a 1975 l82 4 spd manual for reference! And the picture was taken from the drivers side of the car

Last edited by L82 crusin; Jul 6, 2020 at 10:53 PM.

Jul 6, 2020 | 10:59 PM

interpon

Le Mans Master

Joined: Jun 2019

Posts: 7,640

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From: Indiana

Sure looks like the tachometer feed from distributor but one is already plugged in it?

Jul 6, 2020 | 11:13 PM

L82 crusin

Thread Starter

Intermediate

Joined: Oct 2018

Posts: 39

Likes: 2

Quote:

Originally Posted by interpon

Sure looks like the tachometer feed from distributor but one is already plugged in it?

ya I looked at the distributor thinking it was on there but everything is plugged so I was super confused as to what it could be

Jul 6, 2020 | 11:24 PM

REELAV8R

Le Mans Master

Joined: Apr 2011

Posts: 6,284

Likes: 1,170

From: Hermosa

Looks to me like the tach filter has been bypassed or something on yours. Isn’t that mystery plug coming from the metal can bolted to the block?

Jul 7, 2020 | 12:48 AM

bmotojoe

Safety Car

Joined: Oct 2007

Posts: 4,356

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From: Seattle Area Washington

The newer 80-82 tachometer filters had a extra plug that wasn't used on earlier years when used as a replacement filter.
Example:https://www.ebay.com/itm/Corvette-ta...cAAOSwImRYWVaf

Jul 7, 2020 | 07:20 AM

bmotojoe

Safety Car

Joined: Oct 2007

Posts: 4,356

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From: Seattle Area Washington

Looking at the OP photo again, something looks askew the way the connectors are plugged in.....?

Last edited by bmotojoe; Jul 7, 2020 at 07:38 AM.

Jul 7, 2020 | 02:32 PM

MelWff

Race Director

Joined: May 2006

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That's the tach filter connector, the other end is not clear enough to tell whether it is connected

Jul 7, 2020 | 03:47 PM

nearflack

Instructor

Joined: Jul 2012

Posts: 171

Likes: 22

From: Kentucky

Quote:

Originally Posted by MelWff

That's the tach filter connector, the other end is not clear enough to tell whether it is connected

Wonder if tach is working. I have an extra plug similar to that by my distributor on my 1980 and havent been able to figure where it goes either. Tach filter circuit is complete so im still stumped

Last edited by nearflack; Jul 7, 2020 at 03:48 PM.

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Jul 7, 2020 | 04:51 PM

bmotojoe

Safety Car

Joined: Oct 2007

Posts: 4,356

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From: Seattle Area Washington

Quote:

Originally Posted by nearflack

Wonder if tach is working. I have an extra plug similar to that by my distributor on my 1980 and havent been able to figure where it goes either. Tach filter circuit is complete so im still stumped

My understanding it was added to the filter harness as a service port for troubleshooting.