Where are the spark plugs located in the 2002 olds bravada?
They run down the center of the engine under the coils. You can see the coils when you remove the resonator (the thing that says Vortec 4200 on it). One bolt holds the coils in place. Remove coils and change plugs.
Actually you will need to remove the two front tire to to get to them and I would advise watching videos on the removal as two have struts blocking direct assess and you will need a flexible shaft extension or an universal joint for those two at least.
It is pretty complicated (for such an easy task) Buy a 2002 Chevy trail blazer haynes manual. It has the Bravada info in it. in all honesty, I would take it to a shop. I could only get to 5 of the 6 On top of the engine there are six coils lined up from front to back use a 10mm socket to loosen the bolts and below each coil is a spark plug.