Hi all,
I have a 97 Acura 3.0 Cl. I have a remote start that I use quite often and for about a couple months now the tempature inside the car varies. When I warm it up with the heat off it gets up to normal temp pretty quickly. When I get in and turn the heat on warm air comes out as soon as i get to highway speeds the temp hand goes down next to cold. Hot air is still blowing out but the longer I drive the temp hand goes up and the air blowing out gets hotter. I have only replaced the timing belt and water pump all OEM. any help would be greatly appreciated.

 

Your thermostat is bad

 

or possibly air in your cooling system.

 

I had thought about that since I have not replaced it since I have had the car. Would the thermostat make the guage fluctuate like that and thanks for your reply

 

How would I get the air out I dont think the 3.0 has the bleeder screw for the cooling system

 

yes definitely. I've had this happen before, once had to pull off the highway to avoid a freeze. What's happening is the thermostat is stuck open, so when you use the heat, you're taking away engine heat, lowering the temp. When you get on the highway the amount of air going through your radiator is sapping the heat from the system, which can be dangerous, if it's below freezing outside. Wind chill comes into play big time.

To help you if you do live in a cold region, first check your antifreeze with a tester(auto store has em), make sure the coolant is rated for -30 to -40. If you cant immediately fix the thermostat some things that can help when on highways;
turn the heat off
drive slower
if you have some cardboard, block the grill to limit airflow to the radiator.

but just change your thermostat, if your coolant freezes, you can crack your block, crack the radiator, potentially ruin the engine...

 

I dont know where the bleeder is, but what I do with any car is just fill the radiator and have plenty of pre-mixed coolant on hand. Turn on engine, fill radiator as it gets taken in by the engine, once the thermostat opens(might take a some time). Squeeze the up and lower hoses to force out any air in the system. Just take your time.

 

Thanks for your help I have a new OEM thermostat that I will install this week. I will post back

 

I replaced the thermostat this past weekend. Since warm weather is here it will be hard to tell when it cools back down I should be able to tell. Thanks agin for all the input that was given

 

I think the thermostst replacement has fixed the issue.