e38 sd stand alone reduce power

[69camaro5speed]

looking for ideas,this is a rock crawler e38 sd stand alone engine only ,I have turned it inside out for days trying stuff it shuts throttle down under hard loads
if i stay in the throttle it will change the comanded afr to no pe ( like a closed loop)
I have engine dynoed 10 58x 4x ls motors but with another wiring harness and another ecm

[minytrker]

I have never had any luck running E38 standalone with an auto calibration unless it was an actual auto still. I have done hundreds of them and always switch to a manual OS if its on the engine dyno or in a vehicle with a manual or non electronic transmission. It seems like you can get away with alot more on the engine dyno vs once its in an actual vehicle and you start driving it some.

[swingtan]

Does it throw a DTC when this occurs?

Looking at the tune, the VVE looks a bit flat and the WB data in the log tends to agree. It seems to go very lean on static loads which indicates that dynamics are rich and normal fuelling is lean.

Is it registering any KR?

[69camaro5speed]

I have never had any luck running E38 standalone with an auto calibration unless it was an actual auto still. I have done hundreds of them and always switch to a manual OS if its on the engine dyno or in a vehicle with a manual or non electronic transmission. It seems like you can get away with alot more on the engine dyno vs once its in an actual vehicle and you start driving it some.

ok that has cross my mind i may try that

[69camaro5speed]

no dtc codes besides whats in the log,i have had the vvt inside out but if you look at the throttle pedal tps its 100% while the other tps are going crazy it closes the throttle for tq reduction
it has open headers the 02 sensor reads unhappy some times but i have had it richer then this as much as 30%,getting no kr
after looking at it last night maybe its vss limiter needs changes to no vss and other source
also was wondering if some of the tq tables like b3001 could play a part

[gmh308]

Which OS is it?

[69camaro5speed]

I have never had any luck running E38 standalone with an auto calibration unless it was an actual auto still. I have done hundreds of them and always switch to a manual OS if its on the engine dyno or in a vehicle with a manual or non electronic transmission. It seems like you can get away with alot more on the engine dyno vs once its in an actual vehicle and you start driving it some.

do you have a os no. you recommend

[minytrker]

I usually use a 2008 corvette OS but you just cant load that OS. The OS, pedal, and TB all have to match.

[69camaro5speed]

Problem fix Thanks to Taz for his help after working though many problems on this project It had me at a stand still ,now I can work on yard destruction tuning it my poor grass

[400ss]

What was the solution if you dont mind?

[69camaro5speed]

not having the trans controller ,he fixed the tune

[Taz]

What was the solution if you dont mind?

ECM torque limiting, when CANBus communications with the TCM are expected, but are subsequently absent.

[IJ.]

ECM torque limiting, when CANBus communications with the TCM are expected, but are subsequently absent.

Awesome Dude is awesome :D

[minytrker]

ECM torque limiting, when CANBus communications with the TCM are expected, but are subsequently absent.

Thats why I always run the manual OS. Is there an easier way to do it?

[Taz]

I think that using a manual OS is generally the best option, but sometimes a manual OS is not available - like in this case.

[markemac]

I have a transplant cadillac in a off road car, that may be having the same issue, throttle closes down at around 4k nothing i do seems to change it. how was the repair done to the file?