i got code i7, thermostat. the light went off after i bought the new one. so i put it in anyway.
the old thermostat was actually broken so i replaced it.
i drove the car for two days and now the cel light came on again.
if anyone knows anything please let me know. its driving me crazy

 

When my thermostat whent bad i got code 21 for o2 sensor failure because my thermostat was stuck open and I guess it was makeing my mixture ritch (trying to warm up the motor all the time) after I replaced my thermostat I still had the code 21 for a while so I dissconected the battery to reset the computer and that fixed the problem.

Now I get 12, 21(for other reasons [sm=badbadbad.gif] ) and then 55. So I would suggest reseting your PCM (ie dissconect battery for about 30-45 min

 

or pull the 20amp fuel pump fuse in the PDC (its that fuseblock thats attached to the back of the battery tray) for a minute or two, put back in, and start the car. that resets the ecu as well and ya dont lose any radio settings


now.. about that code..
17 Closed loop temp not reached or engine cold too long

this could be caused by a couple things of course. either the thermostat you got is bad (its been known to happen) .. or your coolant temp sensor may be going bad.

also, dont forget that when you change the thermostat, you really should change the radiator cap as well.

 

Oh so thats what code 17 is (I can't belive I forgot I'm such dumb[sm=smiley35.gif]) I get that every once in a while it might stay for a day or 2 but it always goes away and I never notice a difference in the car so I don't worry about it.