can anybody help

[black rocket]

Sounds like heater supply hose against firewall. BTW, have you ever upgraded your hoses?

Anyway if that's the case, make sure you won't over tighten the firewall side as connector is very soft.

Take your IC off and ck under the TB as there are few hoses that are oddly bent and those hoses have tendency to burst as SteveZ had mentioned.

I can't stress enough the importance of replacing 20yr old hoses. While you're at it be sure to ck your fuel supply hoses and fuel damper as it is a #1 cause of engine bay fire.