scanned today..thermostat? prolly replace?

 

That's a start.
I have the same code right now.
The gauge will not move at all on some days, and other it will but the light stays on.
I'm gonna change it this coming Thursday.

For the more knowledgeable members:

What's the worst that can happen with a failing/failed thermostat?
Mine has been out for two, maybe three weeks, I assume that's when the light came on.

 

Mine threw that code once a few weeks ago. It hasn't come back yet, but I hardly drive it in the winter. If it comes back consistently, I'll investigate further.

 

Lack of coolant running through the engine, overheating and all the fund stuff that comes along with it. Warped intake/heads, cracked engine components, bearing failure, crank/cam seizure to name a few...

 

As mentioned before, the worst would be overheating the engine due to lack of coolant.
These thermostats however, are designed to stick in the open position when they fail. The P0128 code is set when the coolant temp does not go above 176*F within a certain amount of time. So, your worst case scenario should really be a lack of heat and poor gas mileage.
Either way, I'd change the thermostat asap. It takes about 10 minutes tops, and is a $7 part.

 

Thanks, and will do!

 

i had the same issue, i changed the sensor. but it only worked like 3 days, then quit for a week. then worked a day, then quit....the worked....you get the drift. I'm quite concerned on what the deal is....

 

I cleared the code, haven't heard anything yet(wife's car). I guess I'll see if it reappears...Thanks for the input & glad to hear it's easy to get it!