A word of warning: When you clean your Throttle Body, your idle will be wacky, do not worry. You will need to re-set by disconnecting the battery and the system will re-learn and you will be back as normal.


Now see the Picture story:

 

I had this groan for a while and when I had the RX serviced for the Brake Fluid TSB, Lexus said I had a hole in the resonator so it made sense that I had this groan when accelerating. So I decided to tear it down and if needed patching, would repair it (but I did not believe Lexus then). And in the process, might as well do the TB cleaning while everything was off.

The TB was not as gunked up to my surprise. Periodic changing of the air filter helps with this TB cleanliness.

2 birds 1 stone. The groan on acceleration has died down and my TB is clean.

WARNING:

Your idle will shoot up the roof. You will need to reset the computer. Disconnect the battery, it will reset and re-learn, your idle will go down to 750 like normal. However you will be re-setting your windows, moon roof and seat settings.

Good luck.

 

Nice job. Did you find it necessary to remove the scoop?

 

I've done this without removing the scoop or any of the front plastic covering. You have to show the air box and plastic tubing who is boss, but it can be done. Also, when I did mine, I removed the entire throttle body as the back side of the butterfly often has carbon / dirt build up as well. Not much harder to do sans the bracket bolt and the bottom bolt closest to the fire wall. Those are a little tough to get in and out.

 

Decided to remove the scoop just to make it easier to yank out the connection to the airbox. There are 2 connections, side and bottom. Next I do this again, I do not think it is needed. Lesson learned.

 

How did you clean behind the throttle plate?

I don't suppose you pushed it open as you would a non-DBW throttle plate.

 

Superb post mandyfig thanks!

 

Yes, gently push from the bottom and clean away.

You will have to do a re-set for sure so it remembers the home setting, if you will. So be not afraid if your idle jumps to 1200 rpm. After re-set, it will be back to 750.

 

Ok, good to know!

I generally turn the key to "ON", and then press on the gas pedal. But as you can imagine, I'm not a big fan of that method.

 

When I did this TB cleaning I was practicing for the spark plug change. Buy maybe I will reserve plug change for the mechanic, about the same time as the timing belt change.

 

Please note one other thing, the PCV valve can contribute to oil and debris in the intake, don't forget to replace it as a maintenance item.

 

no it’s not necessary to remove the scoop