I just used a teardrop-shaped piece of aluminum duct tape (the same stuff that I use to assure that stick-on wheel weights don't fly off). I grab the 'tail' to peel it back when its time for the treatment, then re-apply.

Only needs replacement every 3 - 4 times.

 

55k on car. OCI has been about 3-5k. JLR approved oils but I suspect that the key is not going to 15k for an oil change....use ravenol ecs with the lowest noack rating I could find for a 0w-20. May go to the EHS oil to get the new 6a timing chain protection (frequent changes may cover this anyway now with the older oil type...don't know). Also use top tier gas and bg44k every 2-3k miles. Cheap insurance.

Mechanic who had the engine apart to do the coolant pipes said there was no build up - nothing to do and likely at this rate nothing to do until at least 150 to 200k if ever. He was very impressed (has done a lot with GDI engines....so he knows the drill).

These engines are just really good in terms of carbon build-up compared to some other brands'.