Any datalogging experts here?
I have had a sneaky problem for the last several months. The *only* consistent variable is the cut out happens on first start of the morning and at low speeds/rpms; usually while braking to a stop, but today I was accelerating out of my neighborhood.
The cut-out is gentle; no vibration or shaking. I can start the car right back up and it's fine for the rest of the day.
It has occurred 5 times over 7 months, so I cannot recreate this on demand. At all.
I managed to capture some data from my SCT X4. The only thing that stands out of the battery voltage is at ~14.2V and falls to ~12.5V. Just before this happens, the car downshifts to 1st gear (it's an automatic). Now, the radio still works when the engine cuts-out and I don't recall an interruption when playing music.
So, can the car electronics still function at 12.5V? Meaning, is the battery voltage a red herring and there is something else that is happening and the battery voltage falls in suit?
I attached my data log. You can see the battery voltage dive just after the downshift to 1st gear (Capture 1). Capture_Zoom shows when I restarted the car.
Battery: Green
Measured AFR Bank1: Purple
Measured AFR Bank2: Crimson
Gear Commanded: Orange
RPM: Blue
Throttle Position Actual: Dark Blue
MPH: Red
The only things I can think of are:
1) Battery voltage
2) Vacuum Leak
3) Starved for fuel
4) All of the above + something in the tune
Any other thoughts?
I have had a sneaky problem for the last several months. The *only* consistent variable is the cut out happens on first start of the morning and at low speeds/rpms; usually while braking to a stop, but today I was accelerating out of my neighborhood.
The cut-out is gentle; no vibration or shaking. I can start the car right back up and it's fine for the rest of the day.
It has occurred 5 times over 7 months, so I cannot recreate this on demand. At all.
I managed to capture some data from my SCT X4. The only thing that stands out of the battery voltage is at ~14.2V and falls to ~12.5V. Just before this happens, the car downshifts to 1st gear (it's an automatic). Now, the radio still works when the engine cuts-out and I don't recall an interruption when playing music.
So, can the car electronics still function at 12.5V? Meaning, is the battery voltage a red herring and there is something else that is happening and the battery voltage falls in suit?
I attached my data log. You can see the battery voltage dive just after the downshift to 1st gear (Capture 1). Capture_Zoom shows when I restarted the car.
Battery: Green
Measured AFR Bank1: Purple
Measured AFR Bank2: Crimson
Gear Commanded: Orange
RPM: Blue
Throttle Position Actual: Dark Blue
MPH: Red
The only things I can think of are:
1) Battery voltage
2) Vacuum Leak
3) Starved for fuel
4) All of the above + something in the tune
Any other thoughts?