so i am deciding to seafoam my car today but not very sure which vacuum valve to pull. i know 1/3 of the seafoam goes into the oil chamber, 1/3 goes into the vacuum, and 1/3 goes into the gas tank. if you anyone has done this before can you please tell me what vacuum hose to use.

 

Ummm. I would put it in the gas tank and maybe some in the crankcase but I wouldn't run it through the vacuum. If you put it in the crank case you have to run the engine for a few minutes then change the oil as the seafoam will thin it out.

Seafoam in the vacuum might do more harm than good unless the car really needs a cleaning. It could mess with the plugs and seals a long with mess with some of the sensors. Plus the gas now adays is very good and helps clean the engine so using seafoam probably won't do anything unless the car is really bad. And if it is that bad you are better off cleaning the throttle body and injectors.

I have ran some through by mixing it with the gas but given that most s2000s are in such good condition I don't see any reason to do it unless you have 150000+ miles. and in that case their are better ways of cleaning the engine.

 

Running seafoam threw the vacuum system doesn't seem to really be needed on a S. Get the slightly more expensive spray and and old tooth brush and clean the throttle body and you should be good to go. Just put the stuff you have in the tank.

 

I've ran it through the brake booster vacuum hose with no problem. If you do decide to run it, make sure you have a new set of plugs and oil ready for change soon after.

What you do is remove the booster line, hold it closed with your thumb, have someone start up your car. Tilt the seafoam can slightly til it almost "drips" place it near the booster line, remove your thumb from the booster line and it'll suck in seafoam, almost like a carb. This way you wont have "hydrolock" allowing too much seafoam into the line at once - something to watch out for.

 

thanx for the warning about the spark plugs. i just changed mine. so i guess i wont be seafoaming then.

 

I wouldnt put it in the crank case.. ive done it in the fuel and the break booster b4.. my bro bought a high mile car for dirt cheap.. buick lesabre with 250k miles on it.. added the sea foam through bb vacuum hose let it sit for 15 minutes and started it and you would have thought the thing was on fire.. black smoke like a mofo, smoked for a long ass time.. after that thing ran good sold it for more then he paid for it after he put 40k on it

Dont think you really need to add through the vacuum unless you dont use premium and you sunday cruse every day of the week

 

yeah like you said he probably doesn't need it. and that smoke might mess with his O2 sensor and those aren't that cheap.

Just put it in the gas tank. anything else would do more harm than good on a car that is already running good.