Throttle body/plenum/upper cylinder cleaning Options

[Cuts_the_Pilot]

Hey guys, so I had been researching this Subaru upper cylinder stuff for a while and thought I would give it a go.
I used the can mostly on the Chaser but silly me didnt get any pics, so I have a couple from when i did the GT-four.

Basically the stuff is some serious chemical business that eats away at the carbon, oily build up from the inelt valves to the throttle body. It costs $17 a can from your local Subaru dealership, its in the Subaru service manuals to use it every service (and the dealerships do apparently).


So this is the general process:

Make sure the engine is up to operating temperature.

You jelly of my paint skillz



Step 1: Remove the intercooler pipe, I like to stuff a rag or put a glove over the open pipe (the one that goes down to the cooler) to avoid dropping something in there.

Step 2: Unplug the TPS sensor, TRC plug and remove the throttle cable from the throttle body.

Step 3: There is 4 bolts that hold the throttle body to the plenum, I used a 12mm socked and about a 6" extension. The top two can be undone with a ring spanner but the bottom ones its best to use a socket, there is enough space under the TB to get an extension and socket in there (I used a 1/4" drive set, there MAY be enough room to use 1/2", 3/8" should be ok). I left my throttles coolant lines still attached, it should sit out of the way enough for you to get in there, get a minion to help it needed.





Step 4: Then put the nozzle on the can and go to town, it was pretty disgusting in there (120 000kms in this case), like the throttle body pictured but worse. It comes out as a white foam and the instructions say to empty half the can (the fumes are toxic so unless you want: cancer, aids, ebola and restless leg syndrome dont breathe it in). It was a this point i also cleaned the throttle body .




Step 5: Put it all back together, the instructions say to leave it 5 minutes, by the time you put it all back together it will have about that anyway.


(it comes out this clean, in the 1j plenum there is no low spots for it to sit like in this pic)



Step 6: Start the car and hold it at say 1.5-2k rpm, smoke will eminate from the exhaust, and it will be black, smelly and good for killing kittens so again dont breathe it in. After a few minutes and some free revving the smoke will have cleared and your ready to move onto the next step.

Step 7: Pull off a vacuum line, i used the one that is blocked off in the factory (the one everyone uses for a boost gauge I assume). The car will still run with that off so dont be too concerned about it. Start the car and poke the nozzle into the plenum and start spraying it in. With your free hand (or get the afformentioned minion to do it) hold the throttle open a bit to stop the engine stalling, empty the last half of the can in there. After the can is empty run the car for another couple of minutes to run it all through, take it for a burn around the block to clear out any left over stuff, boost here is a good idea.

You are now done. I picked up another inch of mercury of vacuum at idle and it seems a bit smoother, I have not done any long drives to test fuel economy (the can says it improves, as well as driveability, efficiency etc).


The can doesnt mention removing the throttle body to get in the nooks and crannies, but my thinking is in a long plenum like a straight 6 if you just spray in a vacuum line at one end (especially with the engine off as you do in the first steps) it will favour the end cylinders more.

For the Sake of 17 bux ill be using it again in another 10 000kms or so. Its not harmful to valve stem seals or anything else in there so dont be worried about that. One thing I did think about later is using it in the intercooler pipes, but i'm thinking it would sit in the low spots and thats not ideal.

This post has been edited by Cuts_the_Pilot: Sep 28, 2011 - 12:37 AM

[Smaay]

sounds like seafoam

[Neon90424]

sounds like seafoam

Except it kills kittens

[Cuts_the_Pilot]

Yeah we dont get Seafoam here in Australia.

This stuff was mentioned on a heap of forums so I figured it was worth a go.

Is the process of using Seafoam the same?

[richee3]

This is aerosol, Seafoam isn't. Otherwise it's pretty much the same stuff.

[PolliS_5S-FE]

That was a really crackup read bro. lol @ the aids part

[Spider77]

This is aerosol, Seafoam isn't. Otherwise it's pretty much the same stuff.

Deep Creep....sprayable seafoam....