545OH

Well you did not even address the question. I understand the difference of putting it into the oil v. engine. The question is they also recomend putting seafoam directly into the engine via intake/vacuum line or whatever else feeds all cylinders. They ALSO recomend putting it into the gas tank and running it with a tank of gas. ALSO recomend putting it into the oil. I see obviously the difference between the oil but what would be the difference between the first 2

Also there are hundreds of pages of e90 people using seafoam and nothing but success. I do a lot of city driving and recently had a rough idle that the dealer could not fix. Did seafoam in my tank and has subsided by 80 percent or more. I also do techron as mentinoed but seafoam is good stuff!

Mr.Bavarian

Adding it to the fuel tank apparently "cleans" the gunk inside the fuel lines and the fuel system that was built up over time.
Or something like that. Again, no definitive proof.

simmer

Sorry, misread the question.

So.....now that you explained yourself, think about your question.......the SeaFoam ultimately gets to the same places whether or not you inject it through a vaccum line or in the gas tank. The ONLY difference would be concentration which would be very high shooting through an intake or vacuum. Maybe that is what you need.

I have alot of experience with SeaFoam and like I said have used it for many of my engines with great results. SeaFoam is used for ALL kinds of engines from small 2-strokes to 4-strokes. Running through a vacuum line or direct into the intake is most likely just an alternate way to treat just in case you can't put it into a fuel tank for some reason.

I still wouldn't be shooting it directly into my bimmer's intake though. Why not just run a higher concentraion through your tank? Have you tried cleaning the MAF ?

Good Luck.

545OH

Thanks, that makes sense. I guess in older engines, which it is primarly used for, the carbon build up must be quite severe that diluted stuf through a tank would not cut it and putting too high of a concentration would not work as you cannot put that much into your fuel and still have it run properly with that tank. I like to do mine for prevention more and treat some rough idle and pinging in my exhaust pipes.

I am learnin gthere are a lot of things to do in order to remove or prevent carbon. One thing I realized is I have not driven on a freeway/highway in 5 months and used to drive every day hard on the highway and never had this problem. I took a 50 minute highway drive today, pushing it to redline multiple times and driving it hard. I got home and a lot of the roughness and pinging was gone. I also cleaned my mAF the other week which really helped and ran two tanks of seafoam.

Overall the combo has made everything much better. Gas milage is way up, smoothness is way improved, pinging and roughness is gone, acceleration and overall driveability is noticablly better.

I also did get a fuel system/injector cleaning at the dealer 1.5 weeks ago and added a new kn filter last week so I feel at 36k miles, my car now runs virtually like new. I had the loaner brand new 328 with 400 miles on it and that thing had absolutely no rough idle or pinging obviously. Now my car feels 90 percent back to that feeling and prior to all this it more was like 40 percent of the feeling due to excessive roughness and pinging.

gmcc

I had a K & W on my old Datsun 280Z and I noticed a difference, put one on the vette and didn't notice much differnce. These are seat of pants feelings - not dyno runs. I did have a friend that put too much oil on his and it messed up something in his emission system.

tbal

So did you end up putting gas directly into the engine or what? ROFL, this isnt no lawn mower son.