This is on a 93 Deville. Problem started after cleaning engine after replacing leaky oil line. Car has approx 96000 miles on it. Anyway I cleaned the engine and it just started not idling properly. I've made sure all elec connections are dry and secure.It now will idle sometimes but after a bit it will get rough and die.Off Idle it seems ok but when you let off throttle it might run and it might die. Checked codes and it gave me e26,31,32,53,70. I checked to make sure ground was good and cleared codes. I then started engine and let run until it died then checked codes again an got a e26. I restarted and did the same thing 2 more times. The second time it showed the same e26 but last time I also got e22,70 with the 26. Any help fully appreciated.:banghead:

E26 - Shorted Throttle Switch Signal . That switch is inside of the Idle Speed Control motor. First, make sure the Throttle Position Sensor (TPS) is not binding or sticking. Water could get inside of th eISC motor and shorten the switch. You can disable ISC motor by disconnecting it at the connector. You have to keep your foot on the gas pedal to not let the RPM drop too low so engine stalls.