CEL. Can't figure out what the hell its trying to tell me.

[GooseXRS]

Ok so I have a 1990 stock sohc in my 13 with 208k on it. I noticed my cel was flashing. Talked to the guy I bought it from and he said it always did it. I have read just about everything on how to decipher the code of flashes but nothing makes since. I have watched it for like and hour and it flashes as follows.........
Long= about half a second.
Short= about a quarter of a second.
1long-2long-3short-4short-5short end

I'm going crazy about this.
Please someone tell me what the hell is wrong.
Thanks
Take Care