I recently got a 2002 trailblazer 4.2L i6. It ran fine for 2 days then suddenly died when i floored it for a few seconds and the engine light started flashing. Tried starting it again but no luck, it would run for a second or two if i floored it while starting then die again.
At first i had a P1514 (MAF/TAC System performance) I cleaned out the throttle body and it seemed to be working as it should and the code didn't come back.
Still had the same issue, but now I'm getting a P0300 code. (Random misfires)
While testing the spark plugs it started and ran, turns out when i remove the vortec airbox resonator thing along with the 2 vacuum lines it starts and runs, but sounds like a tractor, misfiring, knocking and spitting smoke out the throttle body. When i connect it back up its back to square one.
What should i look at next?