1990 C4 codes

[Nick90vetteguy]

H33 H72 H13 H22 codes came up I cant make out if its an "H" or not anybody know what these codes mean?

 

[vetteoz]

H is a "history" code ;A code that has come up in the past but is not currently present.


Troubleshooting pg. A

 

[joe paco]

H is a "history" code ;A code that has come up in the past but is not currently present.

Troubleshooting pg. A

vetteoz: thanks! a hell of a lot of info here, someone went to a lot of time and trouble. I'm sure many of us appreciate it. I didn't expect to ever do the DTC stuff when I bought the 91 three yrs ago, but after reading hundreds of comments on CAC, I realized it was nice to know the stuff. There is a world of misinformatin on the Internet, as you can see from some comments posted, so accurate data is welcome. If only we were not inundated with all the damn acronyms!
joe