1981 corvette

[Wayne 1]

How can you read emc codes with a with a paper clip on 81 corvette

Hello to all, I have a question, how do you pull emc codes using a paper clip? I have heard people on here talk about it, but just how would you do it? Thanks

 

[Rob]

Welcome to the Corvette Action Center Wayne!

I'm going to move your thread into the C3 Tech forum for greater exposure to your question...

 

[bill81vette]

welcome to CAC!!!!
enjoy!!!

You you use a paper clip and insert it into the a and b ports. you can read the flashes from the check engine lite...code 12 is flash pause flash flash...which is the every things ok code.

 

[Wayne 1]

Welcome to the Corvette Action Center Wayne!

I'm going to move your thread into the C3 Tech forum for greater exposure to your question...

Thanks, new at this, but I guess you can tell.:L

 

[Wayne 1]

welcome to CAC!!!!
enjoy!!!

You you use a paper clip and insert it into the a and b ports. you can read the flashes from the check engine lite...code 12 is flash pause flash flash...which is the every things ok code.

A little more info. please?

 

[toobroketoretire]

I bought a "code reader" from Chief Auto Supply about 25 years ago; mostly for the booklet of codes it came with. I just push it onto the diagnostic link that is kinda hard to get to (under the ash tray) so the length of it makes it real easy to use. But a few weeks ago I discovered my check engine light isn't working for some reason so I have to fix that first.

 

[Antz81]

A little more info. please?

The a and b ports are the two closest to the drivers side. The connector itself is below the ash tray. The show the codes the ignition must be on but don't start the engine.
The check engine light will then start to flash to indicate the codes. Each code is shown 3 time before moving onto the next.

 

[82ColEd]

Welcome to the CAC Wayne..

There are a few threads here on the CAC talking about it.. See as an example this one:
Pulling Codes

Let us know what codes you get, we'll get you there. We all have started some time and dug ourselves through this..


Stefan

 

[Wayne 1]

Welcome to the CAC Wayne..

There are a few threads here on the CAC talking about it.. See as an example this one:
Pulling Codes

Let us know what codes you get, we'll get you there. We all have started some time and dug ourselves through this..


Stefan

Thanks guys for the info, found out today the emc plug don't work. So at the moment I have no way of pulling the codes. Car runs good and and the idle is good, all gauges read good. The light comes on only when driving about 50mph or 55mph. Stays on a minute and goes off and then comes on alittle later and goes off. While driving around under that speed it never comes on. any ideas? Thanks

 

[Antz81]

If you can't check the codes then it could be a fault with the ECM. Just to be clear though, when you checked the codes you did use the two terminals closest to the drivers side? The link Stefan provided doesn't work for an 81 as it has a different connector. See the diagram below. You can use the little slot as a guide to confirm you are using the correct pins. (As I said they should be the two on the drivers side.) you should hear the M/C solenoid clicking if you have the right ones. Remember to have the ignition on when you do this, but don't start the engine.

 

[Wayne 1]

If you can't check the codes then it could be a fault with the ECM. Just to be clear though, when you checked the codes you did use the two terminals closest to the drivers side? The link Stefan provided doesn't work for an 81 as it has a different connector. See the diagram below. You can use the little slot as a guide to confirm you are using the correct pins. (As I said they should be the two on the drivers side.) you should hear the M/C solenoid clicking if you have the right ones. Remember to have the ignition on when you do this, but don't start the engine.

View attachment 23857

Hey thanks a lot, just went out and done as you said, got code 12 flashed 3 times, then got a code 13 three times, and back to 12 three times. What does code 13 mean? has it got to do with an oxygen sensor?

 

[Tom Bryant]

Yes. Code 13 is the oxygen sensor circuit. You might check to be sure it's plugged in tight and the connection is clean before replacing the sensor.

Tom

 

[Wayne 1]

I want to thank all you guys for all your help, they say you never get to old to learn new things, I know now that to be very true. Again thanks, and if I can ever help you out just ask. Have a great day.