Code 12

[BodesMcGodes]

Hello, I have a 1986 Pontiac Firebird T/A and am having an idle issue. The car stutters all the time until its been running for about a half hour, but even after that, when you press the gas it will bog down and after about a second or so it will jump up to where it should be. Code 12 pops up and is said to be an EST connector from the ECM to the Distributor but nowhere can I find a picture or even a discription of what it looks like. I also can not find anybody online who would sell that part. Could someone describe what the part is? Also if the code could mean anything else I would like to know. The car is a 5.0L 305 Tpi engine.

 

[melsg5]

Not sure where you found your definition of code 12 it indicates diagnostic mode, do you get another code after the 12?.
http://www.obd-codes.com/faq/read-gm-2-digit-obd-codes-free.php

The EST connector is on the distributor, 4 wire connector.