Where is the fuel injector for cylinder 1 located on GMC Safari 4.3 V6

Question

Need to replace the fuel injector for cylinder 1 on 2003 GMC Safari van. I assume you have to go through the inside of the van. Can anyone tell me where it is located and how to replace it? Replaced all three O2 sensors as P0135 indicated that one of the sensors was bad. All 3 new O2 sensors tested good. Still getting yellow light for emissions and short term fuel trim for B1 S2 was 99 vs -7 to +7 for the other two short term trims. Reynaldo indicated that I was dumping fuel some where and to check spark plugs to narrow down cylinder. Long term trims were 0 to -1 on bank 2 and 0 to -3 on bank 1.

Answer 1

it is under the intake manifold, you will find a lot of carbon dirty up in there