I know what the code stands for but what does it mean?

P0128 Engine Coolant Temperature (ECT) Below Thermostat Regulating Temperature ECM, PCM

any answers?

 

it means your engine isnt warming up. staying cold too long. possibly staying in open loop longer than it should.

 

and how would i go about fixing this?

 

first thing that comes to mind is thermostat might be stuck open, not allowing the coolant to properly heat before circulating. also might be a bad coolant temp sensor.

first tell me this... after you have driven the car around for 10-15 min, what is the coolant temp on the DIC reading? should be between 175 and 190.

 

it is around 175-180.

 

you need a t-stat or a coolant temp sensor

 

eh thing is it doesnt come on all the time.

 

are your cooling fans on all the time? does it only come on when its really cold outside? if your temp is 175 - 180 that means it is normal operating temp so i dont know why the cel would be on for that...

 

the fans are on all the time. had it tuned to do that. it seems to only come on for a few minutes if i get on it. and i try not to get on it till its at least a lil warmed up.

 

***dealer***

 

no warranty lol.

 

my buddy just took his in for the same code and they replaced the thermostat

 

dont have your fans programmed to be on all the time. if you have HPTuners, set your 192 fan percent cell to zero. set any higher cells to whatever you want but from my experience they will not turn off if your 192 cell is enabled.

i also retract my previous statement. it may very well be your t-stat. but your DIC shows that the coolant IS in fact at normal operating temp. so i dunno