If you going to run things into your intake that are not gasoline you should give your car a break and run it for a few minutes after to burn through it all and get back to burning gasoline again. By the way MMO in the intake via a vacuum line is done by a lot of the older mechanics to clean something out rather than change all the parts. A lot of young technicians have no idea how to fix something, just change things and the shops they work in are geared to component level swapping for service. How many current mechanics have never seen a rod bearing, surfaced a head or brazed a fitting back together? That type of work has disappeared. I'll give you an example of the difference between us old guys and a dealership. A customer came in with a late model V12 Lambo with a bent valve with a cracked head. The dealer estimate was outrageous, replacing everything in the way including one very expensive head. We machined out the bad metal, and I welded it up and ground everything back to like new and we had him back on the road in 5 days for $2000. $2000 would not have covered the gaskets and misc parts on the dealer's estimate and getting a new head would have been a long time because the dealer would not rebuild a used one for him. I don't think they are equipped to do it. We had him take the car after we fixed it to an independent shop that deals in Lambo's for a checkup and everything is working just fine. Actually the independent shop finished it by doing some fine tuning and then a general service for the whole car. Do you think the Lambo guy is going to see the dealer any more?