I have a 92 4runner 3VZE and I have run a can of seafoam through the brake booster, and when I pulled my intake plenum I noticed that only the back 3 cylinders are the only ones that get affected. I know its been pointed out before but I just wanted to start an actual thread to inform everyone.

I wish I took pictures because it was a very dramatic difference. At least I know that seafoam works wonders but I would recommend to put straight through throttle body or through the PCV hose.

 

sea foam sells a can that has a hose attached to it that you place pointing in the throttle body and re-attach intake hose on top of it. chemical enters through throttle body, cleaning throttle blade and allows chemical to travel all ports in the plenum and most importantly all intake valves. you can also just use a long piece of scrap vacuum hose and a regular can of sea foam, just go slow.

 

I tried the seafoam spray. Not worth the extra $3 or $4. I just poured regular SF straight into the TB

 

Be careful when pouring it in. I tried this method, only to find out most flowed backwards into the intake hose and had a pool of it in one of the chambers. Probably not good. I've used the brake booster each time, mine tends to clean 4 cylinders and only 1 and 2 are not very clean (but still better).

And yes, despite the haters Seafoam does work well.

 

Yea I noticed that when I took off my intake tube that there was some dripping out of the throttle body. I think the best place to put it would be through the EGR tube location in the plenum

 

Yes, EGR and/or cold start injector locations would be ideal.

Hooking another hose onto the PCV valve intake location is a good 2nd best compromise I'd think. Definitely closer to the front/rear bank split than the brake booster connection.

One of my fears w/ seafoam to just partial cylinders (i.e., through brake booster to rear 3 intakes) is that it makes it less hard to read the strain/stumbling seafoam is putting on the engine and increase potential for hydrolock... Probably not a huge concern, but I personally would run two cans of spray through the throttle at once, despite higher costs, than the liquid/vacuum route and know I'm only cleaning half the engine (spray is only a couple bucks more and hits all cylinders)...

I have writeup on here about the Amsoil intake cleaner too. Does a great job at removing upper intake carbon, unsure about piston deposits but probably similarly effective...

 

I tried it through the CSI and it worked very well. All cylinders got hit this time evenly

 

What was your method of running it through the cold start injector? Just remove it and stick a hose in there and dump the sea foam in?

 

I took the nuts off and slightly pulled the CSI back so theres not too much of a leak but a small crack, and slowly poured some in. Its much better this way because you don't have to rev up to do it because theres no bypass there.