2005 Corolla - How can I clean my throttle body?

[MD1032]

Hello,

I attempted to clean my throttle body this past weekend but I ran into a pretty serious problem, and that's that the car will not run without the air intake hose connected to the TB.

So, what do I do? Can I hold the butterfly valve open with my finger and put some TB cleaner on a rag or a toothbrush and just go to town, or do I have to take the thing off?

Thanks for the help in advance, guys.

[mikered30]

Do not force the butterfly valve open with your finger at all, that will mess up the servo. Since you don't want to remove the TB, remove the air intake hose off the TB, put the key to on (not start) have someone or something push the accelerator to the floor and the butterfly valve will open and you can clean it.

[MasterTecInSTL]

Just turn the key on (not start) and wedge the gas pedal down to the floor with a stick or something.

No need to have it running just spray it down and wipe it clean with a soft toothbrush. It will be hard to start and will smoke a lot but trust me it WILL start. Just don't forget to release the gas pedal before you do!

Sorry mike I just realized I said about the same thing you did!

[MD1032]

Thanks for the suggestions. I had a feeling pressing on the butterfly valve would mess something up, so I will avoid that on your recommendation.

I am googling around...it looks like the MAF sensor is upstream of the butterfly valve in these...is that true (maybe this is why it stalled when I disconnected the hose)? I am reading that this is a good thing to clean. It's inside the TB in my Honda, right below the choke, but I saw a picture where an arrow pointed to an object embedded in the air hose going from the air filter box to the TB.

I'm sorry for asking these questions. I have not picked up a service manual yet.

[MasterTecInSTL]

Your mass air sensor is at the air filter box. I found this video for cleaning it on a Celica. The Corolla is similar:

You Tube

You Tube

[MD1032]

WHOA! That's so easy! I know exactly where that is. I'll give it a rip this weekend. Thanks for posting, I looked all over for a video like that.

[MD1032]

I cleaned the throttle body using the toothbrush and the throttle body cleaner with the choke open all the way. Man, it was disgusting in there, no kidding...it took a long time to get it all off.

Kudos to whoever manufactures toothbrushes that don't melt in Acetone, by the way. I truly didn't expect it to survive the encounter.

Also cleaned the MAF sensor with the MAF cleaner. It was easier than replacing the cabin filter! It was only slightly dirty, the wires and little resistor-looking guys were black. No real gunk, though.

Net result? Engine was revving like crazy when I first started it up, then idled very high (1500-1750 RPM) but now the idle has settled down to around 1100 or so. I might just reset the ECU if it doesn't go down more after a few days but it seems to be quite stable the way it is at the very least. Drives the same...of course, but time will tell if this is actually capable of affecting the mileage.

edit: Following up, long term, it was necessary to reset the ECU to alleviate a high idle.

[thatoneguy]

Is the throttle body cleaning the same in the 2004 Corolla? I'm probably mistaken, but I'm under the impression that from 2005 and up they use a different throttle body, so I'm wondering if it's still recommended to hold the gas pedal down to open the valve in the 2004?

[invader]

You can open your cable operated throttle butterfly valve with the pedal, or with your hand on the accelerator control (where the throttle cable hooks up on the throttle body).