Greetings,

I'm trying to get a clean Dyno run, but it seems that no matter what mode I select, when the operator floors the car (2000-3000RPM), it drops a gear every time.
The manual says there is a mode that prevents kick-down, but regardless it still does so.

Anyone heard of a TSB or such to address this?

Also you can clearly feel the switch at the bottom of the accelerator that from what I feel, is part of the lick-down function... Can this be physically over-ridden?

Thanks
Vince

 

From what I've been told, to prevent damage caused by too much load at too low RPM the car will do what's necessary to save itself. Think of it as a Rev Limiter In Reverse.

 

The manual says that you:

Put the Gear Selector all the way to the right in S
Select the gear with paddle shifter

It says the car will stay in manual mode and not switch back. I have not tried redlining it with these parameters, but I have rev'd close to the limit without it auto changing.

My car is a '12 XK, not sure if this correlates to your year and if your S mode operates the same.

 

There is a fuse to pull that will prevent the downshift. See page 192 in our owners manual. I believe it is either fuse 20 or 22. You need to disable the DSC. You can check with a good indie or somebody in the service department at your dealer.

 

Sorry about that I forgot to mention it is the fuse box in the engine compartment.

 

pg 192 in my book is about the Vehicle battery, so I still have found nothing in writing.
F20 is labeled DSC pump and F22 is DSC Valves.

I need to pop the service manual and look for that detent at the bottom of the accelerator peddle. Seems kickdown happens as soon as you hit it.

V

 

You may need to disable ABS too. Going to be dynoing next week for a remap.

 

Did a 5.5 hour dyno session today, pulled fuse 20 from the engine compartment box to disable the DSC/ABS pump. Was able to go all the way to 6500 RPM in 4th gear at 130 MPH with no issues or kickdown though ABS and DSC had some issues after the fuse was replaced. Had to drive around a bit to clear the codes. For some reason DSC seems a lot more sensitive now.

 

There is a soft stop in the pedal that brings you to what I believe is full throttle. Past that point, it takes a lot more force, and you depress a "kick down".

I'd imagine that you are still at full throttle before that kick down switch on the soft stop. I don't know for sure though.