Cadillac Repair: 1989 Cadillac DeVille Error Codes, memory reset, cadillac deville

Question
I have two error codes on my 1989 Cadillac DeVille, E27 and E52.  Do I need to be concerned about these codes?  I just bought this car used and I am worried.  Am I going to have to sink a bunch of money into it?

Answer
Sebastian,
E27 = Open throttle switch - This code refers to the switch in the ISC (Idles Speed Control) that you hear click when pressing the plunger in and releasing it. That switch is what tells the ECM that you've released the throttle, and it needs to take control of the engine speed (set proper idle). This is a non-serviceable item on it's own. You will need to replace the whole ISC if it's actually bad. Before condemning it though, verify that the wiring harness is good and getting a good connection. You can also check the switch with an ohm meter if you'd like. The 4-pin connector on the ISC has 2 circuits in it. One for the motor control, and the other for the throttle switch.
E52 = Memory reset - this is normal to see this in many cars since it will store whenever the battery is disconnected, or power is pulled from the ECM for any reason.