[Guest]

What problems would a thermostat stuck open cuase?

 

[1608]

never warming up - no defroster, frozen fingers.

Steve

 

[Guest]

Would it affect the gas mileage by any chance? On a side note, my defroster still works and I still get heat. Actually, the temp goes up to 210 which is very much welcomed during the winter...

 

[1608]

milage isnt effected alot being cold, but if your temp guage is is indicating 210°, then your thermostat isn't stuck open.

An expired O2 sensor will effect milage , as would plenty of other things.

Steve

 

[316]

What year is your truck? 91 to 96 You can pull up the codes
there is a code for running to cold!

 

[Guest]

I think it's stuck open because the coolant starts circulating as soon as I start the engine. I know this because I looked in the water bottle with the cap off.
Anyhow, I still get heat so I am not complaining. Just wanted to make sure that it is not causing or going to cause any problems. I just need to fix it before the summer.

 

[316]

Fix it now!It can cause the oil to sludge running to cold it can also affect the milage some cause the computer will sence the engine is cold and it will run rich!
What year is the unit????

 

[Guest]

it's an 89. Inspite of the open thermo, I don't think it's running cold. On the contrary, ever since I reverse flushed the heater corethis past October, for whatever reason, it is running hotter this winter at 210 ish than it did last winter at 185 ish. And last winter my heat did not work didlysquat and this winter it gets pretty hot in the cabin. Also, the coolant started turning brown which never happened before I reverse flushed the heater core.

Either way, as long as my engine is running hot (but not over heating), I am Ok then?

 

[Guest]

Yes, it can absolutley affect gas mileage. It can cause a significant decline in gas mileage by as much as 25% particularly in the newer GM V8's. It can also contribute to increased emissions. It's an easy and inexpensive fix and if you are sure that is the source of your prob fix it now, save money and avoid more probs down the road.

 

[krabysniper]

Coolant always circulates thru the expansion bottle even when cold, thats so you get heat first in the winter before the thermostat opens and sends the coolant thru the radiator.