I have a 2017 Infiniti VQ37VHR Q70sport AWD with a cylinder 1 misfire (P0301), here's what's been changed.
- spark plug
- injector
- coil pack
- entire injector sub harness
Misfire is still there, dealer won't warranty it, could it be the A/F sensor? I believe that would trip a P0300 code

94Q45Beast wrote: ↑

Sat May 18, 2019 10:18 am

I have a 2017 Infiniti VQ37VHR Q70sport AWD with a cylinder 1 misfire (P0301), here's what's been changed.
- spark plug
- injector
- coil pack
- entire injector sub harness
Misfire is still there, dealer won't warranty it, could it be the A/F sensor? I believe that would trip a P0300 code

Here is the P0301 diagnostic procedure from the FSM.

It is possible that the A/F sensor could cause the DTC--however that would likely affect more than one cylinder.

I don't see that cylinder compression or vacuum have been monitored, low compression, and/or a leaky or sticking valve, or VVEL malfunction could cause a single cylinder misfire. THe misfire detection monitors the crankshaft's angular velocity, I.e. The problem is not necessarily an ignition or fueling issue.

it could be a faulty or noisy (electrically "noisy") crankshaft position sensor--this was a relatively common problem with Ford's early EECV ("eek-5"; Electronic Engine Control version 5) system used on the '98 to '01-1/2 Mustangs, the ground shield in the co-axial lead to the sensor would break from vibration and cause the ECU to believe a misfar had occurred, when it actually hadn't...

It's been sourced down to wires being shorted somewhere, car won't even turn on anymore or display any lights, had a list of CAN communication codes that dealer ignored with a idle relearn