Thread: Tempature gauge increases when idling

New thermostats don't fix problems in the cooling system unless it was the original problem. If it stays normal after the cooler thermostat I'd consider your old 195 to be defective. A new 195 would have fixed it too, and a 180 will usually let it run at least a few degrees cooler at most times.

My car has never gone above 205 in the year and a half I've owned it, and I've been in heavy traffic in the hot summer. That was with a 195 and 180 thermostat, either or won't affect the temps in those conditions. Any other condition it will usually run cooler if the system is capable of cooling on it's own below 195 without the fans. (since they will not come on til 212) Generally with a clean system, it should be able to keep it at 190° in normal city driving. I've got a new radiator so that may be why mine runs cool. I've replaced many radiators at work, only to find a huge pileup of dirt, dust and grass on it. And that's between the condenser and radiator. That will hinder cooling system performance quite a bit. The fans would run a lot, and it would probably run at around 212 most of the time.

And I don't think your mpg will ever suffer with a 180, I'm pretty sure that's above the fuel trim adjustments.

ive seen a few threads just this winter where mpg dropped, they got a code for running to cold, all with this problem were running a 180 t stat in the north during winter.

Depends how old is your car?

Originally Posted by Scottydoggs

ive seen a few threads just this winter where mpg dropped, they got a code for running to cold, all with this problem were running a 180 t stat in the north during winter.

Mpg's drop greatly every winter with the stock t-stat lol. There shouldn't be a code for a 180, many use it all winter and are fine. Unless the 180 is defective of course. Mine warms up just as quick with a 180 as it does a 195. I know a 160 will set a code in the colder months. Obviously the temp it must get to in a certain amount of time is somewhere between 160 and 180.

Originally Posted by M7x350z

So are you suggesting for me to get a new radiator?

No, if the problem is gone don't worry about it, if it's still happening and everything is original, a cooling system flush is always a good maintenance idea, and you can clean the radiator exterior. I like to remove the cooling fans since water should be sprayed in the opposite direction to clean the stuff that came in from the front. Spray a cleaner from the rear of the radiator and front of the condensor and let it sit, then spray it down good with a hose from the front and back a few times. Most only have a little build up and should get clean from this. You should see dirt and stuff wash away.