Best vacuume line to use for seafoam
 

Good day everyone,

I did the seafoam yesterday using the brake booster vaccume line, but I've also heard to use the PCV line right in the front of the car, which one it's the best to use in your opinion

Unless your car is very new and has very low miles the correct answer may be "none of the above." If it works at all on our cars, reports here are that you must do it early and frequently.

I tried using the Berryman's three step kit, which includes cleaner for the throttle body, cleaner for the intake valves (like Seafoam, but stronger) and fuel tank additive for the injectors.

This was at about 60,000 miles. Bottom line, I probably got some benefit from the throttle body cleaner and maybe some from the tank additive to help clean the injectors (although good fuel probably does fine for that), but the B-12 product (and probably Seafoam) proved absolutely worthless in cleaning crusted on carbon on the intake valves.

You can give the Seafoam a try, but don't expect much if your engine is not very new.

On direct injection engines like ours, where no fuel ever gets into the intake manifold and through the intake valves, and given the crud that recirculates into the intake manifold from the EGR valve, the carbon build up on the intake valves is extreme.

There are separate threads here with excellent "how to" advice on the correct way to remove the intake manifold and directly clean the intake valves.

Good luck with the Seafoam. Just don't expect it to do much good. Either way you listed will get the Seafoam to the valves. It's just not going to be strong enough, or be in contact with the valves long enough to do much good. Most of the "smoke" you will see coming out of the exhaust will actually be the petroleum distillate in the Seafoam. It will look like it's removing a lot of carbon, but looks can be deceiving.

brake booster is it. PCV is under the IM, a no-go. We are DI, so valves don't get it. Look for the thread on how to clean the valves.