Originally Posted by tabetha

So long as you're sure the engine is getting up to proper temp, and the stat working as it should, feel the in out hoses as they go from the engine compartment through the bulkhead to the heater box, if they are both warm, then inside the car, have a look at the flaps to make sure they are moving when you operate the lever for vent/floor/screen etc, and also the hot/cold one, it may just be a cable off, worst it could be is a totally blocked matrix, but even this would still produce luke warm heat.
tabetha