Fuel Trim Cell PID

[VetPet]

Could someone explain this PID and what information it could provide if scanned? There's no information available in 'more info' when you right click on the PID. From what I understand it will show you which fuel trim cell you are in under different engine operating conditions. How would you use it to build a MAP that would help you to tune your engine? What other parameters would you need for it?

[joecar]

From B3809 and B3810 you can draw up a 4x4 array (RPM vs MAP) and an FTC value in the range 1..16 identifies a cell on this 4x4 array.
In the Scan Tool, go LS1/LS6->Long term fuel trim cells and you'll see the cell number definitions.

It proves more useful to just build a Scan Tool map for LTFT (RPM vs MAP) without using the FTC pid.

[ringram]

Its also useful to know when you look in a log if the vehicle was at idle, accelerating or decelerating. It can help narrow a problem down to certain tables.

[VetPet]

Guys. I saw the FTC definitions in scan tool under the LS1/LS6 LTFTcells. I have logged the LTFT's and created a Map in scan tool. My numbers are way positive compared to before I installed my CAI system. Got my LM-1 kit the other day and can't wait to start tuning. April is still a long way off but at least I'm learning more everyday. I should at least have a good grasp of the concepts by then and be more prepared.

A great Christmas and New Years to all.

[deezel]

If you are running a closed loop tune, you can use the trim cells to optimize the cruising ranges of the vehicle. The boundaries of the trim cells can be adjusted (as joecar mentioned above) so that the PCM has a separate cell for the commonly used operating conditions - idle, slow accel, slow cruise, medium accel, medium cruise, etc.

[pkincy]

If you are running a closed loop tune, you can use the trim cells to optimize the cruising ranges of the vehicle. The boundaries of the trim cells can be adjusted (as joecar mentioned above) so that the PCM has a separate cell for the commonly used operating conditions - idle, slow accel, slow cruise, medium accel, medium cruise, etc.

It would be interesting to see what others are using for the Cells.

I moved my rpm up on both boundaries about 400 rpm. Since I idle at 900 I wanted the lower cells to at least hit the idle and I run an M6 so needed the second boundary to be a bit higher also. I did leave my Map boundaries stock.

Any other thoughts?

Perry