Cadillac Repair: engine codes, cadillac deville, service engine soon light

Question
my service engine soon light just came on. i was told how to pull codes but have no money to buy a guide to find out what the codes mean. i have a 1990 cadillac deville. the codes that i am given are 8.8.8, . .E, E49,  .E.E,  E49, and .7.0   
please help me !!  

Answer
Ok Let's ERASE all your codes and see if any come back.

1. Ignition ON, Engine OFF.

2. Push and hold the OFF and WARMER buttons until all the segments on the display illuminate and as soon as the codes start to appear, Push the OFF and HI buttons and release them until you see .7.0.

3. Turn ignition OFF.


Now repeat your original sequence to see if any codes reappear and let me know what they are.