Help Request: P0300 99 Suburban K1500 LT 5.7

Discussion in 'Suburban / Yukon XL / Escalade ESV' started by tahoesteve666, Jun 17, 2020.

  1. tahoesteve666

    tahoesteve666 Full Access Member

    Likes Received:
    Nov 24, 2015
    Just put a fully rebuilt 5.7 engine back in and adjusted the CAM Retard Offset to +1 degree using Torque app.
    No other codes except P0300.
    Have limited data access to ECU at moment, but some data includes, at idle and warm engine:

    Intake Manifold Pressure at 36 kPa (10.6 in Hg)
    MAF at 7.22g/s
    dont have fuel pressure
    dont have any Trim Data
    Scanner has clearly indicated misfires on cyl 5 and 7, the others cylinders are solid.
    I've only swapped plugs (41-993) and cap/rotor so far, no change.
    I also sprayed carb response
    Tomorrow I was planning on swapping some plug wires.

    Any other suggestions to help debug this?
    Last edited: Jun 17, 2020