Driving to work last night my engine light went on. Truck ran fine, no power loss or other problems felt/noticed. Went to the auto parts store and they checked for the codes.

Only one code popped up..... P0128.. I was told that it was related to the thermostat and coolant. I purchased a new thermostat, (what could it hurt, owned the truck 4 years and never had to change it.)

So was I given the right info??

Thanks for any input.

 

My Haynes manual only covers 2002-2008 and for that code it says "Thermostat Rationality" whatever that means.....

 

Basicly, after looking around on google, you probably did the right thing by changing thermostat. It seams like it means that the stat was sticking open and not allowing water to heat up..

 

It means that 'the coolant temperature does not rise by a calibrated amount over a calibrated amount of time.'

 

THANKS FOR THE INPUT FOR THOSE THAT DID. TRUCK IS BACK RUNNING GOOD.