This would be ODB 0 on a stock 91 civic dx. I Was guessing until the car was shut off. This true?

 

codes are stored in the ECU until you physically reset the ECU by removing power to it for about 10 seconds - the Check Engine Light will go off when the key is turned off and will stay off until another problem is detected by the ECU, however, the codes remain in the ECU

 

For Ev Er!!!!! Lol, if you know what thats from...

What he said^^^^^

 

So if the CEL was illuminated yesterday and it was turned off and restarted it should still be stored in the ECU?

 

Yes. Just as jlicrx stated, until YOU PHYSICALLY reset the ECU it will still be stored in there.

 

Great! didn't know that. Got my two codes, 10 and 15. Intake sensor and Ignitor...

Thanks!

 

is your ECU LED flashing 10 times, pausing, and then flashing 15 times? - if so, then you are correct, IAT and igniter