My 1997 Saturn all cool air no Hot air

[David Wells]

Hey this is my first time on this site so do not get pissed at me lol.

My problem is went I am driving around town the heat is on but it is cool air coming out but soon as I get on the highway it blows out warmer air but not hot air .
Just would like to know if anyone here had this problem and if you can help me thank you

I was told that it maybe the heater core but someone also told me that it maybe the thermostat some help would be great thank you again.

[VS1400]

A clogged heater core is a possibility, but not very common problem on the S series cars.

A thermostat is a much more likely and much less expensive possibility.

Where's your temp gauge at while your driving? Normal running temperature should put the gauge somewhere near the middle of it's travel.