my car has been having problems warming up to full temperature. the coolant level is fine and i bled the system, and i just replaced the radiator cap, which I think was part of the problem because now the upper radiator hose feels solid after driving the car. but the temp gauge still drops all the way once i start driving and it will go up once i'm sitting at a stop light. is the thermostat stuck open?

id try the thermostat.

thermostat is the temp regulator, definetly the place to start. Plus not having the motor run at temp can cause other drivability & wear problems.

make sure the temp sensor/sensors aren't frucked....you can test them pretty easy. thermostat too...

+1 Thermostat. Another symptom of a bad thermostat is if your temps get too low while cruising at high speeds in cold/wet weather. That's how I first discovered mine was mess up. I changed it and the first thing I noticed was that the car warmed up in like 1/3 the time.

i just had this problem on mine. the thermostat had broke and the system was in open loop at all times. it sucked i had to change this while it was snowing out side while i was on vacation away from home..

yeah i was thinking it could be a faulty temp sensor causing the temp gauge to just read low, but the heater blows pretty cold, so i'm thinking it's probably the t-stat. just wondering if it could be anything else i overlooked.

look at my post above.

i had the SAME thing happen to me.


at idle it would warm up. but after you start driving it would cool down. in cold weather it would go to the C no heater.

my Tstat had broke leaving the valve open there for causing the coolant to work in a open loop. (always moving threw the system) instead of letting it close and keep it all warm.

wow, just changed it. the exact same thing happened, the t-stat was broken on one side. thanks for the help guys!

/ubbthreads/images//graemlins/applause.gif for crappy t stats. i was like /ubbthreads/images//graemlins/dunno.gif when i pulled mine out and saw that.

Im having the same problem...I think i'll change mine /ubbthreads/images//graemlins/idea.gif

buy OEM ones, autozone ones suck as well as advance/checkers.

yeah i had no idea they could break like that. unfortunately, i did buy a parts store replacement just for a temporary fix. you can tell how much smaller the diaphragm is on it than the oem one. seems to be working ok for the time being, but i guess we'll see.

yea i too had the same problem and checked it out and it was a fail safe that had stuck open, so i hope my car was never overheated reall bad /ubbthreads/images//graemlins/uhh.gif

Dead givaway if the car warms up standing still and then won't stay warn once you start moving. I have to replace the thermostat every 4 to 5 years in the winter when they start sticking open.

The aftermarket ones seem to can cooling problems in the summer because of the smaller opening so I stick with the OEM part.

I have measured some aftermarket thermostat valves and there is at least one that is bigger than the OEM one. /ubbthreads/images//graemlins/smirk.gif

how much are the OEM thermostats? mine is also going on me too.

Quote:
I have measured some aftermarket thermostat valves and there is at least one that is bigger than the OEM one. /ubbthreads/images//graemlins/smirk.gif



Part numbers or you're lying. /ubbthreads/images//graemlins/smile.gif

I put in an autozone low-temp and I've had absolutely no problems with it. If you're concerned about them not bypassing enough coolant you can just enlarge the small bypass holes on the side. The valve opening will still be the same size but you'll have a small increase in flow over the entire temperature range.

That tiny hole is mainly to release air when filling.