Sooo i was driving on a highway when i realized the car was getting pretty hot. i had the a/c on auto so i put it to the lowest temp on full power but barely anything came out. and if i left it on like that for long enough, smoke would start coming out. any suggestions what the problem is??

 

Are you certain it was smoke (smoke has a strong smell and a signature)? Or perhaps it was water vapor.

My first thought is a coil (evaporator) freeze up. Make sure you don't run your A/C on recirculate too long in hot humid conditions. This can cause the coil to freeze up. Also, make sure your dash vents are open and flowing air.

After the car has been sitting for a while, try your A/C again to see if it is working.

 

lolk vapor is better word. yeah it works now but this happens form time to time. is it something i should get checked up?

 

When you run your A/C on recirculate too long, humidity builds up on your cabin because of breathing, heat from people's body's, and not being replaced. This increases the moisture in the A/C intake and therefore, causes more condensation on the coil - which can freeze. If you see water vapor and/or smell a moist smell coupled with a distinct lack of cooling, you most likely have a coil freeze up.

The normal action of the A/C when set to AUTO is to run on recirculate until cabin temperature reaches the level set by the driver. If you set your temperature too low, it will run on recirculate virtually the entire time until it gets to the low setting. Try using a higher setting, say 68 or 70 degrees, when you first turn it on. The other thing you can do is to exit recirculate mode.

If it is working fine after having sat for a while, the next thing I would check to make sure things are working correctly are the vents. You want a good and even flow from your vents. Blockage can also cause coil freeze up because it slows and reduces the amount of air going across the coil.