Temp. Gauge All Over The Place...Air or T-Stat?

[JoeHoe_SHO]

Okay, this started happening after I replaced my CPS/Water Pump. The needle will go to or a little over the N, creep back down just under the O, then go back to the N, and fall again. This will happen a few times...the more it happens, the more it drops, until it drops to inbetween the M and the A. It will still rise and fall after that. I'm thinking its either air bubbles in the coolent system or I need a new T-Stat. How do I get air out of the system? Where is the T-stat in these MOFOs? Near the throttle body right? I don't think its in any of the hoses but then again, I don't really know. Any and all help is appreciated! Thanks thumb

 

[Machspeed]

Its prolly your tstat. Do you check the coolant in your radiator every morning to check the level? You can grab the upper hose and gently sqeeze it to get more coolant in the system. More likley you need a new tstat. When you run your car and it gets hot, does it look like the hoses are suckin them selves in? The tstat is a simple job. Follow the upper hose into the engine, see where that bent metal piece goes into the engine? Theres two nuts holding it on, top and bottom, thats where the tstat is. BE CAREFUL when replacing the tstat, people have broken the WHOLE tstat housing. But its really a simple job. Good luck. thumb

 

[AutoSHO]

Its air. Get it good and warm and then let it sit overnight. In the morning pull off the radiator cap and see if there is space between the top of the radiator and the cap (filler neck, I mean). More than likely the problem is that your thermostat does not have the jiggle valves to allow air out, and when you replaced the water pump a whole bunch of air got into the system and is now having a tough time getting out.