Quote Originally Posted by vailskier3 View Post
did my coolant change today, and when i started her up with the new green prestone coolant, i threw these codes. any ideas why?

[PCM] P0116 - Engine Coolant Temperature (ECT) Sensor Performance (Old) (Immature)
[PCM] P0134 - HO2S Circuit Insufficient Activity Bank 1 Sensor 1 (SES) (Pending) (History) (Immature)
[PCM] P0520 - Engine Oil Pressure Sensor/Switch Circuit Malfunction (History) (Immature)
[PCM] P2432 - Secondary Air Injection System Air Flow/Pressure Sensor Circuit Low (Pending) (Old) (History) (Current) (Immature)
Hi,
I am the tech manager at Prestone and a mechanic as well. I doubt any of these are related to changing your coolant. If you tell me the year of your car and send your email address to me at Jay.Buckley@Honeywell.com, I will look up and email you troubleshooting instructions for each code.