Heater core clogged

2004 aztek. Heater core is clogged. Tried to flush it out with a garden hose and air. Didn't get anything to come out either side. What do you guys recommend to put it in the heater core to break up the clog?? Buddy of mine said some places flush out heater cores with some kind of acid? Thanks for the help in advance.

2004 aztek. Heater core is clogged. Tried to flush it out with a garden hose and air. Didn't get anything to come out either side. What do you guys recommend to put it in the heater core to break up the clog?? Buddy of mine said some places flush out heater cores with some kind of acid? Thanks for the help in advance.

I have not seen a flush product that will unclog a completely blocked heater core. If back flushing won't clear it out, you'll most likely need to replace it.

The key is to "backflush" the core....if you are flushing in the same direction as normal flow, you are doing it wrong.....