You got to pull out the dash to access THC heating/cooling system getting the dash off is the fun part its all comon sence once you see the part
Hayes Repair Manual, $20 tops.
Heater coil
heater coil is good conductor of electricity
The heater coil is located behind the dash board. You will have to remove the dashboard to get at the heater coil
Usually misfires can be attributed to a bad plug, wire or coil.
Go to NAPA and buy a repair manual for your specific car.
Clarification of terminology- Heater core not heater coil. And Yes there is a very good chance that it may be leaking.
The heater coil and a heater core is the same thing. Hot water circulates from the engine and through the heater core then back to engine generating heat for your heater system.
the coil is behind the motor
heater coil is good conductor of electricity
This is a job that needs supervision so as to not mess something up and costing a bunch to repair. Get a manual form the parts store or AUTOBOOKSONLINE.COM
I found the answer on AutoZone.com There was a section on repair info and then go to Heater Core GM Blazer/Jimmy/Typhoon/Bravada 1983-1993 Repair Guide. It has a detailed guide and pictures. Good Luck!