My car's SES light came on recently, and with Autotap's EFILive I saw that the code that it threw is DTC P0128 (ECT). I installed a 160* T-stat about 5 months ago, but now that the mornings are very cold (mid 30's in the morning here) it might be taking the engine coolant a little longer to reach the target value.

During the same reading, the ECT was about 140 degrees, at start-up ...

Have any of you experienced this before? Or do you think it might be a faulty t-stat?

Thanks in advance!

 

That DTC code is: Coolant Temp Below Thermostat Regulating Temp

I never had a problem with the 160* in mine, but who knows?

Anyway, you can look up any DTC code on this site:

http://www.actron.com/code_lookup/index.php