i have a 1994 del sol si with the stock d16z6. so i get in my car today, and i let it warm up. the needle gets to where its supposed to, so i start to leave. not 50 feet down the road i look down at it, and it is already half way down to C. another 50 feet, and its all the way down to cold. it does this every winter! what is wrong with my car? is it the thermostat? the fan switch? help please!

 

dude lets take a step back and think. ur driving in cold weather, as u drive the airflow cools down the coolant through the radiator and also cold air over the engine. mine does the same thing ive checked everything and its all good.. i would be concerend if it never warmed up at all

 

cold weather will aggrivate a bad t stat. if it is already bad, the cold weather makes it worse.

every honda i have owned, i have to replace the t stat hahaa for the same reason.

 

when you turn on the heater is the air cold or hot. my car has been trippin it says that it hot when i turn the heater on all i get is cool to warm air. huh go figure.

 

so do i need a new thermostat? cause my brothers civic heats up, along with all the other cars in my family. the heat gets warm, but never really hot

 

if your heat doesnt make you sweat on full blast i would check your thermostat and change it. there like $10 from autozone, or $25 if you must have one from honda. my car does the same thing, but my heat stays hot.

 

change the thermostat for starters. then flush and bleed air out of the cooling system when you refill it - you could even tip the ratio a little more towards coolant than water so you don't end up with ice in your radiator.