yupSeafoam works. I suppose at 200k you would have a lot of build up and it probably isnt as good of an idea.
yupseafoam is pretty much always beneficial. I mean it's only $8.
The only question is if you have a high mileage vehicle, do you risk finding out that that sludge and buildup is all that's keeping your car running?
Remember to change your oil afterwards.
and you can use any vacuum line which is pulling air towards the upper intake.
Do you put it directly into the oil? Or a vacum hose or something that someone said earlier?I have done mine at ~65k and then once or twice since. I don't like the idea of putting it in my gas, and when you do it in your oil, drive around for a while and then go change it right away so it doesn't eat away at seals. Seafoam when left for a while can cause harm.