im sure this has been ask already but I was woundering what works better to dump seafoam in the throttle body or the vac line
an is the car suppost to be running while u do this on not
sorry if it a repeat question

 

Engine definitely should be running or else it will just end up in the crank case.

I prefer dribbling it down the throttle body as it will pull it into the center of the intake and distribute it more evenly to all of the cylinders.

You can also pour it through the PCV valve hose or through the brake booster hose. Either will work. The PCV valve vacuum source pulls off of the driver side of the intake as does the brake booster vacuum source. This will tend to distribute the product more to the passenger side cylinders (runners cross in the lower intake manifold).

On older motors which have the throttle body pointing towards the front, I have done several different things. One is to use a hose and a small funnel to direct the seafoam into the throttle body, but the easiest way is to just pull off a vacuum line from the throttle body area. With the long runners on the CPI motors, it will give plenty of time for the product to mix and be distributed evenly to all cylinders.

 

well i have a 2000 with 169.000 miles on it will it hurt any thing i have just recently put new plugs in it an should i do an oil change before after or don't it matter