HELP with cleaning the intake valves myself.
 

At the 60k mark, when I have to pull the surge tank off the engine to replace the plugs... I think I might like to clean the valves and intake ports by hand. Can a Lexus tech chime in with some advice here:

1) How difficult is it to remove the intake manifold, and what supplies do I need to reassemble the motor? (Gaskets, gasket seal, etc) I've never pulled off an intake manifold before, but know it has to seal properly when it's put back together.

2) I assume once the manifold is off and the plugs are out, that I can turn the engine over by hand, fill intake ports (with closed valves) with top end cleaner and scrub them with a wire brush. Will I have good access to the valves?

3) I would just use rags and a shop vac to pull the cleaner out of the intake port, and for good measure let the car sit overnight in case any liquid made its way into the combustion chamber.

I'm at 50k miles right now and I dont' have severe symptoms - just some stumbling at idle, probably 2x a month. If it's not a big deal to clean the valves I'll do that and start using an oil with a low NOACK (low volatility / low evaporation) rating. BG44k additive should clean the piston tops and overall things should be pretty decent.

Insight??

Not sure how to do it by hand, but why not just use Seafoam? Easier and you get to create a fun smokescreen for your neighbors! :)

I don't believe that Seafoam through the intake does a great job cleaning the intake ports.... I've seen threads where owners of GDI engines tried Seafoam and ultimately had to tear down the head. There is not a lot of proof that it actually works if you have significant carbon build up.

Does anyone have access to a Lexus document showing how the intake comes apart? (Like a TSB that requires this step?)

here is the Spark plug replacement document which has all the instructions on how to remove the intake. Have fun and let us know how it went.

meis250 -- Thanks for the attachment but it only shows how to pull off the "surge tank" (this is the plastic upper manifold). The part I am more concerned about is the aluminum lower manifold -- in Figure 11, this is the alumium part with six circular holes. With the lower manifold removed, I will have more access to the intake port and valve.

Has anyone removed this part? I need to know if it's just a dry gasket under there, if any RTV gasket goop is required, the torque values for the bolts and tightening sequence, etc.

If I get all the information necessary to carry it out, I'll definitely do a DIY writeup for the forum.