From what mk378 says, I not sure you will have an option.

 

In the Haynes manual, there is a chart of which lights are on versus what the code is for. So you don't have to know binary.

 

I have the kind with the sigle LED. I pulled a 14 and 17 with the 89 computer in. So I plugged in the puter from the 90 and now I get code 14 and the same idle up and down issue. Puter from the 89 was a 37820 PM5-A08 and the 90 was a -A09. Maybe I need to clean the IAC?

 

Good progress. Also check for faulty wires and connectors. If they check out okay and cleaning the IACV doesn't help, then the IACV might need to be replaced.

 

Cleaned the IAC, checked my vacuum lines and made sure they were all in the right place, did the spray the vacuum lines for leaks test, checked all wiring connections and everything looks fine, but I still have the code 14. I guess I'll replace the IAC but that will have to wait till Sunday.

 

Do you still have the idle up and down issue? Also, did you clear the previous CEL code from the ECU before retesting?

 

The idle issue has calmed down some, it still goes up and down - just not as much. I did reset the puter and the code came back as soon as I started the car.

 

Just curious, did you find that the IACV was heavily clogged with gunk and, if so, how well did it clean up?

 

It was not really that bad. The screen was covered a little, but I have seen MUCH worse on other vehicles. A couple sprays got the thing cleaned out.

 

Someone said that air in my cooling system can cause the issue I am describing. Any thoughts on that theory?