The only access to the heater core on a 96 S10 blazer is by removing the entire dash asm. It is not accessible from the engine compartment. If you are not familiar with disabling the the air bag system, do not attempt this repair.
remove the cover on top of the engine. the wies are om the igniter coils remove the cover on top of the engine. the wies are om the igniter coils
How to Remove the Steering wheel From a Chevy Blazer 2001
Right under the throttle cover.
rip it off
i have a 93 s10 blazer and had to replace the heater core recently, it is a pain, and it helps to have another person there to give you a hand, you have to take the entire dash out, remove the heater core cover, undo the brackets and undo the hoses from the heater core, the worst part is removing the dash and remembering where all the wires go if you do this job yourself i sugest taking pictures as you go along
below glove box remove heater/air conditioning cover then remove blower motor cover
how to remove timing cover with heater pipe attached 92 olds 88 3.8l
Remove the glove-box door. Behind that is the heater core cover on the interior, passenger side of the firewall. Remove that cover and there is the heater core. Open the hood and look where the heater hoses enter the front right passenger area of the exterior side of the firewall. Disconnect the two heater hose clamps and you can then remove the heater core.
Disconnect the heater lines going into the fire wall from under the hood. Remove the panels from under the dash. At this point you should be able to remove the heater cover and remove the heater core.
Remove the inside cover of your glove box, 4 or 5 screws, then you will be at heater core cover, remove 7 screws from cover, and if you have disconnected your heater hoses, the heater core will pull right out. Just did mine thanksgiving day. 20 minute job
under the plastic cover on top of the engine, you will need a torx fitting to remove the cover, then the coils are on top and spark plugs below the coils, very easy to replace, coils are just 1 10mm bolt each
drain coolant, disconect heater hose's, remove glove box, remove heater core cover, remove heater core. reverse order to reinstall.