Sorry, I just pulled it from the general GM codes. 80 Corvette is obviously different.

 

Another mystery,, I changed out the HEI distributor for a new one with good wires, the old one had burnt and leaking wires. now when starting with the new dist the engine light seems to be flashing randomly while running instead of the solid light. I run the test now by grounding the terminal at the computer and I get only the code 12 and no trouble code after that just code 12 repeated again and again so really lost now Rusty

 

This is all on a 1980? I thought that the 81 was the first year of the ECM and E4ME carb, 7 pin ignition module and so on.

 

I'm not in a position to get to my Shop Manual at the moment. I know that codes are automatically cleared after 50 engine starts. I think the only way you can force the clearing of codes from the ECM, is to disconnect the battery.

Your check engine light will remain lit as long as there is a problem in the system. If the problem is intermitant, the light will stay on for a few seconds after start up, and then go out. Even though the light has gone out, the ECM will store the fault code. These code(s) will only be cleared after 50 engine starts (without the problem recurring), or if the battery is disconnected.

I'm not sure what to make of this situation. Are you sure that your not getting multiple codes when you ground the terminal? Remember that upon grounding the terminal, code 12 will flash 3 times, and then any fault codes will flash. The fault codes will also repeat 3 times, so if you have 2 fault codes stored, you will have 9 series of flashes. Fault codes will flash in numerical order, starting with the lowest number code. If you have a code 21 and 23 fault, the light will flash 12 three times, then 21 three times, and then 23 three times. I can't recall if it then starts over, but either way, this can be quite a few flashes to keep track of, and it's pretty easy to loose track of them.

GM first used the Computer Command Control (CCC) system on 1980 California emission cars, including the 305 powered 1980 Corvette. 1981 was the first Federal emission use of the GM CCC system and the E4ME Q-Jet (though I think there was some limited use of the CCC in certain 1979 GM vehicles too).

 

Couldn't stand it anymore,, I threw a stock Q jet non comp controlled on the vette and she runs beautifully, the exhaust smells nearly as clean as my brand new Nissan Titan. Oddly enough with all the terminals unplugged from the e4me carb and just sitting there, there is no engine light. The air cleaner is so massive a smog guy would have to take the thing off to realize there is no computer controlled carb under there, ill hide the e4me harness of course. So whatever ill roll the dice on 40 bucks and see what happens. I haven't given up completely on the factory emission system, but need some relief for now Rusty

 

You can reset the codes by disconnecting the battery.

Go throught the troublesooting proceedures shown above. If the issue is the MC Solenoid, they are still available and are fairly easy to replace. The ECM can be bought on Ebay. But it may be something as simple as a loose ground or corroded connector.

The computer controls the Carb AND the distributer timing advance. If you only change the carb, the timing advance will still be wrong -- driveability will suffer.

 

Well said. And nice to know that those gizmos are still available. Can you recommend a supplier?

 

The E4ME carb is pretty easy to work on, not much more than a stock Q Jet. It does require a few special tools / gauges to set the mixture control solenoid though. You can usually get these off of ebay for about $20.
Heck if you want, you can send me the carb and I will put a kit into it. You pay shipping both ways and the kit plus float. Takes me about an hour to rebuild and do the settings since I have done this several times.

Send me a PM if interested.

 

That sounds like an offer you should accept.

 

I appreciate it I will have to do that thank you