have got a bit of a problem some reason my EF's transmission is slipping in the cold for the first 100meters of driving ,

The fluid is brownish to black , and the fluid level is a bit on the low side have only cheeked it when hot and it is just above the add 0.5L on the hot side

Would anyone know if having 100ml to little can cause such issues ? , i will be topping it up tomorrow evening as currently i am working on other odds and ends to fix on the car and want to test it while its cold as well

But would adding a electric shift kit DIY style, bump up the pressure's in the cold and help out with this problem at all? if it keeps giving grief after fluid top up

Fluid should be pink to cherry red. If it is brown to black then it is stuffed.

Auto will need a full flush and filter change. BTR autos are very sensitive to low level fluids. Just above "add 0.5lt is not 100ml. It is more like 400ml.

Get it serviced ASAP or you will need more that a shift kit. Which by the way do not bump up line pressures.

change fluid

So not keen but it looks to be quite straight forward to drop the pan and change the filter

should it be a bit of extra insurance then just topping it up ?

Don't go any distance without topping up. But, with your fluid in that state, an urgent fluid and filter flush and change is in order.

Simply draining the trans leaves most of the old fluid in the internal passages - a waste of time and money. It needs a proper flush. This CAN be done at home, but it's a bit of a process. Much easier taking it to a specialist who can do it for not a lot more than it would cost to do it yourself.