Originally Posted by c-bass

I've been using Liqui Moly products the last few years. Engine flush at every oil change and jectron and valve clean alternating every few tanks of gas.

Having cleaned out some of the mayo and gunk from the top end of M54s when changing a valve cover gasket I honestly don't see how much cleaning a liquid mixed with oil would do.

Thre's been quite a bit of elbow grease used to clean the build up off and anything that's gunked up and hard I'm pretty sure wouldn't budge with anything less than a brush. I've even poured a bit of cleaner directly on the gunk and it's not like it just washed away.

Do I believe anything horrible would happen? Probably not, but I don't think any of these cleaning solutions are nearly as effective as I would have originally thought.