Heat Problem
 

My 01 SL1 is starting to have problems with the heater. It's taking a long time for the heat to kick in even when the temp guage says my car is warmed up. It's always warmed up pretty fast until the problems started happening. Once it does kick in it turns to cold air when I drive slower (30 mph or so) and when I stop. Then when I accelerate and get to faster speeds it turns warm again. Anybody have any knowledge as to why this would happen?? Any help would be great! Thanks!

Sounds like coolant is not circulating through the heater core properly. You may have a partial clog in your cooling system.

I would start with a cooling system powerflush and refill -- and see what comes out (literally)

+1 for the recommendation for powerflush and refill -- Derf has the answer

Im having the same issue with my daughters 2002 SL1 and have flushed the system replaced the water pump and thermostat and still cant seem to find the problem. When I flushed the block nothing came out and it was the same when I flushed the heater core. Car gets warm but very little if any heat is allowed into the cabin.

The pump seems to be working fine. If you take your hand and put it on the upper radiator hose it swells alittle when you rev the engine same with the lower hose. The temp gauge seems to be working fine and she hasnt had any overheating problems.
The heater hoses are also cool to the touch even after idling or driving the car for 20mins.

Any Ideas??

This does seem to be a bit unusual, because all the Saturns I've run across - the heater system was VERY EFFICIENT. This deserves more thought ....

Thanks Im at a complete loss as to why it is doing this.

I had problems with air in the system getting stuck in the heater core.

Sounds probable -- I suppose you could manually "burp" the system by unhooking the outlet of the heater core and ensuring that the you do not have air trapped in there when the coolant is circulating...would make a bit of a mess but seems worth a try