NEWB: Water temp gauge doesnt move !!!

Hi everyone, I need some help with my dad's 2001 Olds silhouette. Just recently his water temp gauge dropped and hasnt moved. It only moves when you turn the key, maybe about 1/8 inch and then drops again, so im guessing the gauge works.

It came up with an error on the obd2 reader. P0128 (coolant temperater below thermostat regulation). So we dont know whats going on with it, the heat and a/c work and the engine revs are normal. But the front cooling fans run non stop, both of them.

I went to the dealer and they said it may be the thermostat. Ive searched this forum on the montanas as well and some ppl have had success in chaning the thermostat and other have found other problems such as the intake manifold gasket>???

I bought the thermostat and I plan on installing it today. Im stuck out of ideas on how to get to it.

1. REmove the air tube
2. REmove throttle body
3. Remove some of the coolant
4. --- stuck... how do i get to the bottom screw of the thermostat pipe?
Theres some exhaust bypass with a shield. ANybody know the type of key/tool that i need to just loosen the bottom screw.

I also want to find out from other past experince how to truly tell a thermostat failure from anything else. (person with the intake prob had a p0128 come up)

Any advice on the procedure would be greatly appreciated.

Thank you,
Ciprian

I'd forget about the thermostat and replace the temp sensor. It's likely your problem and is fairly easy to replace. If you are quick you don't even have to drain your coolant (although you will make some of a mess). Removing the t-stat housing without removing the cross over pipe is possible, but very difficult.

o sorry guys, i got the problem solved via the montana section, it was the thermostat.

yes coolant leaked everywhere, but the problem is fixed. If the gauge is dead and the cooling fans run non stop, its the thermostat.. TRUST ME i just finished the swap. Not too bad.
Just
1. remove intake
2. remove throttle body
3. Then unscrew the top bolt of the thermostat pipe
4. Loosen the bottom one, you will have room with the TB off
5. Then the pipe just moves up and the thermostat is right there
6. Swap it out and follow steps in reverse, just be careful not to drop any tools
7. Fill up the cooling system, open the little bleeder on right beside the engine and the one on the t-stat pipe. Let the coolant drip through the system, you will see it come through the bleeders. Than start the car with the bleeders open
8. Watch the fluid flow through the bleeders and keep on topping it off.
9. GIve it a good 10 mins and then close the bleeders.
10. The engine temp should rise to about normal and a little bit over and then drop to under normal as you drive.

My dad took it to work today, a good 150km and no overheating or anything, topped off the coolant at work and then it was fine on the way back, im guessing some was still lost along the way.

Easy repair about 6hrs with everything, bleeding and test drives.

Good luck guys.

Ill be on www.hidplanet.com/forums (http://www.hidplanet.com/forums) and www.dodgeintrepid.net (http://www.dodgeintrepid.net)

Thanks for all of the help,
Ciprian