02 Sonoma service engine soon lite
02gmcsonoma
12-08-2005, 02:35 PM
Code PO128 kept coming up.Changed thermostat and will see what happens.Any other repair suggestions for this code??
gmc2003ZR2
12-16-2005, 10:40 AM
P0128 - Coolant Thermostat (Coolant Temp Below Thermostat Regulating Temperature)
I just added coolant to my zr2 and the temp is runing around 160+- when it usually runs @ 240+-.
Is it safe to drive if coolant resivior is full?
How do you clear this code?
Do I need a new Tstat?
Does it need to be cleared by a shop computer?
Is it hard to change, if you are mechaniacally inclined)
any help is much appreciated!
:eek7:
Matt
I just added coolant to my zr2 and the temp is runing around 160+- when it usually runs @ 240+-.
Is it safe to drive if coolant resivior is full?
How do you clear this code?
Do I need a new Tstat?
Does it need to be cleared by a shop computer?
Is it hard to change, if you are mechaniacally inclined)
any help is much appreciated!
:eek7:
Matt
GMMerlin
12-17-2005, 02:09 PM
P0128 - Coolant Thermostat (Coolant Temp Below Thermostat Regulating Temperature)
I just added coolant to my zr2 and the temp is runing around 160+- when it usually runs @ 240+-.
If you added coolant, check for a leak
Is it safe to drive if coolant resivior is full?
YES, but see answer above
How do you clear this code?
You need a bi-directional scanner....you can try disconnecting the battery, but that doesn't always work
Do I need a new Tstat?
Possibly, but I would check for leaks first
Does it need to be cleared by a shop computer?
Answered that one already
Is it hard to change, if you are mechaniacally inclined)
No
any help is much appreciated!
You are welcome
I just added coolant to my zr2 and the temp is runing around 160+- when it usually runs @ 240+-.
If you added coolant, check for a leak
Is it safe to drive if coolant resivior is full?
YES, but see answer above
How do you clear this code?
You need a bi-directional scanner....you can try disconnecting the battery, but that doesn't always work
Do I need a new Tstat?
Possibly, but I would check for leaks first
Does it need to be cleared by a shop computer?
Answered that one already
Is it hard to change, if you are mechaniacally inclined)
No
any help is much appreciated!
You are welcome
serpentracer
01-01-2006, 06:31 PM
first of all your temp is normal at 160
240 is not
you can also clear codes by pulling the ecu fuse.
my truck had this code before I cleared it and it has not came back on. I have a scanner and it clears codes. I have not tried the fuse deal.
if your temp is running at 240 you probably need a new thermostat. and make sure you have sufficiant coolant levels in the radiator and overflow tank.
240 is not
you can also clear codes by pulling the ecu fuse.
my truck had this code before I cleared it and it has not came back on. I have a scanner and it clears codes. I have not tried the fuse deal.
if your temp is running at 240 you probably need a new thermostat. and make sure you have sufficiant coolant levels in the radiator and overflow tank.
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