I’m a newbie and have learned so much from this forum thanks! I have read on methods to clean the intake valves with CRC and it has come apparent that the easiest method is to use the brake booster vacuum line as recommended by OzXFR. But another member XJ8JR asked if “Using that brake vacuum line, wouldn't the intake on just one bank get cleaned?” That is also my question.

Can anyone shed some light on that or make any recommendations to the best way to do an Intake Valve carbon cleaning on the V6SC? Thanks in advance.

 

I personally have not seen any effective way to remove carbon build up on the valves using chemicals injected into the air flow through the manifold.

The most effective method to decarbonise the inlet valves on direct injection engines is to remove the inlet manifold/supercharger and use walnut shells to blast the carbon on the back of the valves. The engine must be rotated to ensure the valves are closed on each cylinder in turn. Once the carbon has been loosened, it can be vacuumed out and the manifold/supercharger reinstalled.

 

How often do you recommend doing that? Every 50 or 100k miles?

 

Depending on how the vehicle is driven and maintenance frequency, it can be anywhere from 60,000 miles to nearly 100,000 miles.

 

Do you believe there would be any benefits to using a chemical cleaner in a maintenance or prophylactic manner? I have noticed that the JLR service department is all to eager to offer these services as a maintenance measure at an extra cost.

 

From what I read on BMW forums, which had this issue much more prominent and acute, is that a) more frequent oil changes b) periodic chemical treatments will greatly delay the point where walnut blasting is necessary.

Based on that information, I do chemical clean every 2 years using BG system and change oil a lot more frequently on my F-type. We will see by 2026 to 2031 if that made any difference. My theory that it is possible to stop early stages of buildup but once it gets past certain point only mechanical (e.g. wallnut media) removal is possible.

 

Nup, it cleans both banks.
The brake booster vacuum line nozzle just happens to be on the LHS of the SC (looking from the driver's seat) but it feeds the entire SC not just the LHS.