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Throttle Body Cleaning w/Pics

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69K views 60 replies 29 participants last post by  Mistermike87  
#1 ·
The MAF cleaning thread started moving towards a Throttle Body cleaning so I decided to go ahead and clean mine and take a couple of pics along the way. First off I dont live in a real dusty environment and I do run a K&N air filter that I clean every 5k. I have also started using the Lucas oil fuel treatment in every tank of gas to see if it worked and so far I think my mpg has gone up slightly.

First off here is a pic of the Throttle Body that is just under the palstic engine cover:
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Loosen the screw that holds the clamp tight around the neck of the throttle body, its the one with the baby blue plastic clip. I also used my compressor to blow off any loose dust from the engine.

Then loosen one of the screws and remove the other screw that holds the intake in place and remove the intake from the throttle body:
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This will expose the opening and butterfly in the throttle body. Note that the TB does not appear that dirty but you can see a bit of soot:
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Take a shop towel or rag and place it under the TB opening and spray this stuff:
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into the opening while working the butterfly with your fingers. You will notice some black stuff that naturally comes off and out onto the rag. Then carefull reach in and wipe out the inside of the intake working the butterfly, make sure you dont get your rag or shop towel stuck in the butterfly. This is what my shop towel looked like after the wipe:
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Once you wipe out the inside put everything back together pretty quickly and start the FJ. It will hesitate at first but quickly even out. Take it for a spin around the block and to clear out the cleaner. Hope this helps.

:cheers:
 
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#3 ·
First off I dont live in a real dusty environment and I do run a K&N air filter that I clean every 5k.
Just to clarify, and have some fun:
Do you just knock out the filter each time you change the oil? I assume you don't do a complete spray-down and re-oil of the filter every 5K. That would be a little OCD. If you are OCD, please don't write me a letter, because I know you won't ever stop. :rofl:
 
#4 ·
It depends on how dirty the filter is and how OC I feel that day. I have only cleaned the MAF sensor once and the throttle body two or three times and I have over 43k on the FJ. :cheers:
 
#8 ·
PG[/img]into the opening while working the butterfly with your fingers.
What do you mean by working the butterfly with you fingers? Opening and closing it, wiping both sides of the butterfly? Also, how far back "behind" the throttle body do you need to clean?
 
#9 ·
Okay, nice job on the write up.

Summarize why the throttle body needs
to be cleaned:

-allows free movement of the throttle
plate so throttle pedal is not "sticky"

Others?

Does it improve gas mileage to
keep this area cleaned up?
 
#10 ·
The amount of soot buildup in the throttle body will not effect pedal feel, since the FJ like many new cars uses "drive by wire" throttle control. This means that the gas pedal is connected only to a sensor, and there is a solenoid/motor controlled by both input from the gas pedal and the vehicle computer that opens/closes the throttle plate.

Regardless, the control motor can move more freely and in smaller increments if the throttle body/plate are clean, and the ring of buildup around the throttle plate can interfere with airflow at idle and low engine loads since the throttle plate is nearly closed in these circumstances.
 
#12 ·
Beware! You can mess up the servo motor that controls the butterfly if not properly executed! I would recommend taking the TB off so that you can clean the other side of the butterfly without having to turn it.
 
#13 ·
Which way does the butterfly move? After toyota cleaned mine I went in to check it. I wanted to see how "clean" they got it. As I looked in, the top side seemed to be pushed in (away from the opening) a little bit. So to check it and clean it a bit more, I pushed in the top. I assume normal operations it only moves one way. For cleaning can it move both ways?
 
#14 ·
The butterfly will only move in one direction. There is a spring that will force it closed against a stop when the engine is turned off. Without the stop, the spring would lose its spring load.
 
#16 ·
A couple of posts above I mentioned I wanted to see how good of a job Toyota did when they tech cleaned my throttle body. I went in using the method of forcing open the butterfly with a rag covered screwdriver sprayed with cleaner. It seemed as if it was "clean" for the most part. After viewing this thread and mentions of upsetting the motor that controls the butterfly, as well as not being able to really get 'er clean without removing, I decided to remove the throttle body today and clean from both sides. I have installed the AFE TB Spacer (mostly to create a tighter fit for the CAI tube which has been known to pop off the air box without the spacer) so that needed to be cleaned as well. You can see here that "cleaning" the TB without removing cannot really get the other side. Of course if you do not have the spacer installed you do not have all the little cut outs and grooves to worry about, but there would still be a fair amount of soot left on the other side. Along with not wanting to destroy the motor by forcefully moving the butterfly, removing the TB is really the only way to do a great job of cleaning. And it is SO easy so why not!?!?!?

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#17 ·
Thanks for the post awood. I think removing the TB for cleaning might be the answer to my earlier question about a "supercharger safe" TB cleaner. If I remove the TB, I don't have to worry about running TB cleaner through my supercharge and I'll do a much better job of cleaning too.
 
#18 ·
Yeah no worries! Removing it is really your best bet.
How is that supercharger treating you? It is something I might consider in the near future.
 
#20 ·
With an electric throttle body, never move the blade - force it - by hand. You can damage it. It's easy enough to remove the TB from the plastic intake

If you want to clean around the edge of the blade, with it off, have somebody you trust get into the driver seat and turn the key to Ign On

Do NOT attempt to crank the motor!

There will be a loud whining noise from the electric throttle body. Floor the gas pedal and the butterfly will open wide. As your assistant keeps the gas pedal floored, you can spray TB cleaner on the butterfly and use a shop rag to clean the edge of the butterfly

Once the TB is cleaned, make sure the TB housing isn't going to interfere with anything and have your assistant release the gas pedal and turn off the ignition.

You can then carefully bolt the tb back onto the plastic intake manifold. Do NOT go too tight or you could crack the housing!

Note: a brick on the gas pedal can replace a helper and is probably more reliable anyway

Sometimes when I clean the TB, if its got enough grunge on it, when I restart the Check ENgine and the VSC/Trac lights are on. Several drive cycles will clear the lights
 
#21 ·
You can then carefully bolt the tb back onto the plastic intake manifold. Do NOT go too tight or you could crack the housing!
Torque specs as written in the AFE spacer install instructions are 10ft lb. I assume those carried over from factory specs? Seems about right for the application.
 
#22 ·
Why not remove the TB to access the backside of it and get it fully clean?

Its only 4 more 10mm bolts and it comes right off. I did this when i installed my supercharger. Pretty simple.
 
#24 ·
Where is the motor, is it built into the body or is there a linkage to disconnect?
 
#27 ·
I remove my TB as well when i clean it. If there is enough grunge especially at the circumference of the blade/body interface, when you clean it you will get the christmas tree

Several drive cycles will clear the lights, I've never had to disconnect the battery. I suppose I should next time i clean the TB, will force the computer to learn new fuel trim maps quicker

One nice thing about the christmas tree is that Trac is disabled. The FJ seems to have a lot more power when it's allowed to spin tires
 
#28 ·
This & PCV are the last items on my DIY list I need to try/do. So far I did plugs, diff oil (I may never do it again, getting skids off & on was the worse experience ever when they're banged up!), MAF cleaning ($10.00 vs $370.00 quote from dealer, Arrrrgh!), and brakes. Saved a TON of $$...did I miss anything?
 
#30 ·
Here are results for u guys. The FJ has 39,000 on it never been done before
front-dirty
Image


front-clean
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back-dirty
Image


back-clean
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The Fj runs great now! Done with MAF cleaned , K&N filter cleaned reoiled.

note: for those that haven't done this yet, its 4 bolts 10mm ,2-gas lines thatneed to be removed and electric connection off TB. It is very easy better than dealer or mech to do it (cheaper peace of mind)

BILL:rocker:
 
#31 ·
Thank you for the photos

I don't remove my TB from the actual vehicle, and leave the coolant hoses attached. There is JUST enough slack in the coolant hoses to allow you to keep the TB a good 2 inches away from the intake manifold

I put a couple of shop towels under the TB when I spray the TB cleaner on it
 
#33 ·
Shouldn't hurt just don't do it the other way around and use TB cleaner on the MAF.

There were a few that mentioned not cycling an electric TB by hand to prevent damage but not much beyond that.
What type of damage are we talking about? Complete failure, incomplete butterfly operational range, erratic idle?
 
#34 ·
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