What are these codes for 92 cadillac deville ff,f40,f,e,e48,e52,ee,888,70?

Hello williamcole7: My name is Roger and I will help you. The code 888 is a test code. This tests the L e d's of the dash cluster. All segments must light so you can read all numbers. The 70 code means the system is ready and able to function. The ff code is a current BCM code and is happening at the moment. The f 40 code is a BCM history code and means it was a stored problem or something that has happened. The f 40 code is for a air mix door problem. THe BCM would set this if you had an A/C problem. The E 48 code deals with the EGR system fault. I would check for a vacuum leak at the EGR solenoid. The hose is prone to deterioration do to heat from the engine. Code E52 deal with loss of voltage. A dead battery or a disconnected battery cable will always set this code. None of these codes will keep the car from running.The repair schematics are to extensive to send in a reply. Should you need further help ao assistance I will be glad to help. Please rate the answer. Thank You for using Fix Ya. Roger

1992 Cadillac deville fuel dash readings are not right, reads wrong and states wrong gas amount, used etc. amounts. Can't tell how much gas in tank. So is this in the cluster under the dash or sensor in gas tank. It is a guessing game as to where have gas in car.