What sort of intake manifold cleaning?

[PandaBear]

So I'm thinking about cleaning the IM due to old age (187k corolla and 225k integra) and the intake valve deposit common on direct injection (IS250).

Considering either seafoam applied by spraying through the brake booster vacuum hose, squirt through the throttle blade (not sure how to do it on a drive by wire car like IS250), or a can of carb cleaner through the throttle blade.

What would work the best?

 

[bepperb]

A few things worth note. The IS250 has a single port fuel injector in addition do the direct injectors so it's not plagued by intake valve deposits like other DI engines. Even though it's drive by wire, it still has a throttle body. So, you would inject whatever cleaner after the MAF sensor, and before or after the throttle body like any other car. I haven't heard of any DBW systems being damaged in this way, by solvent getting into their electronics.

People seem to like the seafoam or plain water. I'd probably go seafoam through the brake booster on your two older vehicles, and leave the IS alone.

 

[PandaBear]

bepperb,

I though only the 350 has dual injectors being partially port injected, and 250 is only direct injected.

 

[1993_VG30E_GXE]

I wouldn't bother with anything, without scrubbing it off by hand with laquer thinner and a wire brush or loctite varnish remover, there's no way any products can get that stuff off. It's caked on there so hard, it'll just be a waste of money. I'll take some photos for you.

Bead blasting it could also get it out, maybe putting it in a jet sprayer booth.

 

[The Critic]

Amsoil PowerFoam would be a good option. It is a aerosol foam type cleaner that should cling to parts a bit better than the liquid SeaFoam. If you ever make a trip out-of-state, Mopar Combustion Chamber Cleaner can be purchased at a Dodge dealer.

 

[benjamming]

Whatever you use, change the oil very soon afterwards.

 

[JTK]

Originally Posted By: bepperb
..So, you would inject whatever cleaner after the MAF sensor, and before or after the throttle body like any other car. I haven't heard of any DBW systems being damaged in this way, by solvent getting into their electronics.


True. No damage from the cleaner, but you don't want to work the electronic throttle by hand from under the hood. If the throttle position sensor(s) don't line up with the accelerator pedal position sensor, the system freaks out and defaults to limp mode. You need a helper to feather the go pedal when cleaning these.

Joel