Kinda curious on why my old 90' HF had a awesome heater and the 91 Si i have now doesn't blow but luke warm air... any ideas? Fan speeds work...

 

anyone?

 

Are you sure the control valve on the inlet is completely open-the cable may not be pulling it fully.

 

Make sure the control valve is opening all the way..{it is outlined in the center of pic}
or also the thermostat could be hung open and not allowing the engine to warm all the way up.

Or go to:*click here* for more troubleshooting tips..

 

also make sure you have enough coolant. That happened to me and my coolant was low....and it fixed the problem

 

thanks guys

 

also try back flushing the heater core. LOTS of junk tends to build up in there.