[ZZZZZR1]

Welcome to the forum and congrats on your purchase!

Original injectors are likely part of the cause, but your likely in need of a few things.

Injectors (get stainless steel ones from Fuel injector connection)
Coil packs (4 needed, I prefer OEM)
Spark plug wires (Jerrys Gaskets)
Fuel Pumps (Chevy Suburban's have the same)
Actuators (2 needed, these can rust and have rubber inside) Good idea to replace
plenum Gaskets (Jerrys)

Please post pictures of your car! Any plans?

Headers? Exhaust?

If you need more info on parts, I can post up or PM you.

Cheers

David