Temperature gauge goes up and down
 

Hello everyone. My girlfriend's 2001 Eclipse GT has been having issues. The temperature gauge will rise to the top spot as if the car is overheating. However, it will then lower to normal and may go back up and then back down. I'd like to know if anyone knows why this is happening and what I can do to resolve. She had an EGR valve control malfunction error which I cleared. I then cleaned the EGR valve but the temperature issue still continues. Also, her car will not always blow heat. It may be heat at one minute and then it will go to cold and then it may or may not blow heat again. I don't know if they are related or not. I'd appreciate any help that can be provided.

Thank you.

RE: Temperature gauge goes up and down
 

this could be several things. start with the cheapest and check from there on.
first off - check your coolant level
second - replace your thermostat - it's only about 15 bucks and take less than 20 mins to insall.
third - are you getting any smoke out of the tail at all? we are looking for white smoke in this scenario. also check under your oil cap for any white milky residue.
If you aren't getting any heat it could be bad heater hose. If none of the previous work, i'd have a shop look at it. If its a simple heater hose than it shouldn't be more than 50 bucks for them to replace (if you have any mechanical skills what so ever, you could do it for the cost of the hose).
If none of these seem to help, it's either a bad water pump, or a blown head gasket.

RE: Temperature gauge goes up and down
 

Deff check your coolant level, sounds like your low and check for leaks. Alsomake sure you dont have any air pockets.

RE: Temperature gauge goes up and down
 

Thank you dsm1990gsx and RCJr9186 for your responses! I have a couple stupid questions. I'd like to know how to know when to stop filling the radiator with the 50/50 coolant / water mixture. Also, I need to know the best way to get the coolant hose that goes from the radiator to the engine off of the engine to replace the thermostat. I did take RCJr9186's advice by buying a thermostat. However, I cannot get that hose off for the life of me. I am using a small pair of vice grips to squeeze the clamp, but I cannot pull or pry the hose off. I tried prying it witha screwdriver that is on the long side with limited room and am getting nowhere. Is there a tool that you can recommend that will get the job done better than buying a shorter screwdriver? This is proving harder to me than taking the EGR valve off, changing brakes... hell, an engine replacement would be easier at this point because that hose has Hulk Hogan's grip. I'd appreciate any answers that you can provide.

Thank you!

RE: Temperature gauge goes up and down
 

Try removing the cap. The negative pressure in the lines will stop you from pulling it off.

Also, while the car is running, look for bubbles. Run it for quite a while with the cap off to see if the level goes down and bubbles surface.

RE: Temperature gauge goes up and down
 

It's either thermostat or you have a blown head gasket. You won't always see smoke out the exhaust from a blown head gasket though. If you notice that white film though, it's a little too late. You'd then need an engine cleaning. Best bet is the replace the thermostat and if that doesn't work, possibly EGR Valve or Blown head gasket. What part of PA are you from Clarion or Forest county?

RE: Temperature gauge goes up and down
 

Thats Hilarious my 2000 GT does the same exact thing..Ive changed the thermo, Radiator, Next task for me is going to be the water pump. Good lucka nd keep me posted if u find a fix