I've noticed the last week or so its taking longer then normal for the car to come up to full operating temperature (but it does get there eventually) - so i'm thinking a bad thermostat. Is there any codes/CEL's that come on for a bad thermostat? Or is there any way to check it out before calling up the dealer (make sure i'm just not going crazy)?

I was checking out the service manual and was reading that the thermostat is closed, goes half open at a certain temp, the full open if things get really hot. So it seems mine has failed in the half open state?

The other thing i thought is maybe there are thermostats in the oil coolers that may have went - but there are no thermostats in those things right?

 

hmm i see P0126 and P0128 in the service manual but if i'm reading that right they only go on if the ECT remains under 160 degrees for 6 hours??