VigCS

Alright guys - so I pulled my car up to warm up for 15 mins before leaving work, turned the heat on full blast. Time to leave, I hop in my car and my heat isn't hot. My car is sitting at about 150*, it usually runs at 195. So I go "huh thats weird". I start driving home, and my needle jumps to 225, heat gets really hot, then it goes back down to 180 and it continues to alternate between these two temps, heat going hot, cold, etc. Any ideas? I'm thinking I just need a new thermostat. This all happened over a period of three miles of driving. (This is all on an aftermarket AutoMeter A pillar temp guage)

I replaced my water pump about two months ago, as well as my radiator, fan and fan shroud so those can't be the problem. So...I'm thinking it's either a bad thermostat or I have a bubble in my cooling system (which doesn't make sense cause it's run at a steady 195 before tonight). My coolant reservoir is at the normal level. I should also add that this has been the coldest night of the season thus far. It's about 10 degrees out with windchill.

Any ideas? Thanks! I need to get this fixed as it's my DD.

mustnglvr

How cold is it where you are?

VigCS

10 degrees with windchill, coldest night we've had so far.

2 kwik

do you have a stock fan? if so clutch maybe gone also I'm thinking you have a partial plugged rad with it heating up as you drive and cools while idling

5.0stanger

Check you fluid levels...if they are fine, I would say a new stat is in order.

mustnglvr

Is it possible you dont have enough antifreeze in you mixture? Coolant slushing in areas of the system would cause that.

VigCS

It wasn't cooling down just during idle - it was heating up and cooling down while driving as well. Like I said, my coolant, radiator and water pump are all new so I doubt it'd be plugged.

redmustang83596

Definatly sounds like a thermostat to me, get a new one, really cheap and really easy to fix, try that.

PRO50SC

Shoulda replaced the stat when you did the other coolant system work. Woulda saved ya the hassle now.

VigCS

Well a stat isn't a big deal at all. Do you all think thats what it'd be?