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P0128 code

TDgrand

New member
I have just relocated from Florida back to Michigan!

I had my Grand Prix 2005 N/A shipped on a truck. It has been cold these past few days (30's) and I took her out for a drive.

15min into the drive I notice low coolant temp and then engine light P0128. I have a 180 thermostat since Florida was so hot.

I assume the code is because of the 180 stat, should I put back in the 195?

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128, is that the slow heat up code? If so, likely your therm either stuck open and didn't heat up fast enough or it's bad and didn't heat up fast enough. I believe even your year is only looking to heat up to 160F, thing is..it's at a certain pace.
 
128, is that the slow heat up code? If so, likely your therm either stuck open and didn't heat up fast enough or it's bad and didn't heat up fast enough. I believe even your year is only looking to heat up to 160F, thing is..it's at a certain pace.
P0128 definition per Autozone, "coolant temp always to low"

Would a new 180 Tstat be sufficient in michigan weather? Or should I go back to 195? I have no mods just a straight N/A motor.
 
I'd run a 195 to help with fuel efficiency etc since you are stock. A fresh 180 would do the trick..but a 195 is likely going to treat you better all around.
 
Thanks I purchased a 195 yesterday, new steering pump will be going in as well. Thanks to the NAPA reman crap.
 


When I bought my 2001 GT, I was getting that same code all the time, and the temp gauge never left the bottom line, or just barely. Bought a new 195, and found a 180 in the car. Replaced, and no problems since. Uptick in efficiency too, like Bill said.
 
195 is in and code is clear. Looks to be running great and temp is where it should be.

New NAPA reman steering pump whines like a B@$#%. They will replace it and give me another one. Should have bought a junk yarder 1 1/2 years ago.

Almost ready to just say screw the NAPA warrenty and get one from a yard.
 
So I went to put on the new power steering pump and it seems the threads to the pressure hose are slightly stripped.

I did everything I could to make sure that I did not strip them out and they don't look to bad. It just wont grab.


The pressure line looks pretty easy to change out with removal of the sway bar for easy assess. I would like to change the return line as well cause it looks old and might as well.

How do you remove the return line hose? It seems to wind along the frame and back to the rack.
 
you mean you rounded the line nut? vise grips. done.

the return line is a hose clamp on the end of the hose where it ends on the pump. theres a tube off the pump it clamps too.

watch out for the knock sensor wire clipped to the back of the p/s pump too.

take the belts off. then i took the tire off and got under it and took the lines off first, ( have a small pail to catch the fluid that will come out) then unbolt the pump, take it out. then take the pulley off, then put it back on the new pump, re install, then put the lines back on.

when putting the line back on, the threaded one, if you cant get it to catch, turn it back wards till you feel the threads click and drop, then turn it clock wise. give a little wiggle if need be to catch the threads squarely.
 


watch out for the knock sensor wire clipped to the back of the p/s pump too.

Best step/advice a guy can give to another when doing a ps pump.

On doing the lines at the rack. Leave the sway in place.. lower the back of the cradle abotu 2-3 inches and you'll have the room you need.
 
Sounds good, my car too wouldn't move beyond the 1st line when I bought it except when I was idling or driving less than 10MPH. The exception with me was I had a 160 degree stat in mine.
 
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