Cleaning throttle body

[jcampo788]

Greetings all!

I have a slight hard start occassionally on my T4R, V6, 318K.

I have decided that it is likely the throttle body, considering when I replaced the battery last weekend it had a hard idle when I started it post new-battery install.

I saw a video on Youtube where someone cleaned the throttle body and blade without removing it. I then saw the tutorial on here where it was removed (four bolts).

Can you clean the throttle body without removal?

 

[waypoint]

You can, but it requires caution as the throttle butterfly is on a motorized actuator you can damage by opening it manually. Also very difficult to wash out the gunk without pushing it down the intake and into the engine.

The extra time and effort of wiping it with small paper towels would likely be more than just unbolting the TB and bolting it back up with a new seal and torquing to spec.

 

[jcampo788]

By seal, do you mean the gasket between the throttle body assembly and the motor?

You can, but it requires caution as the throttle butterfly is on a motorized actuator you can damage by opening it manually. Also very difficult to wash out the gunk without pushing it down the intake and into the engine.

The extra time and effort of wiping it with small paper towels would likely be more than just unbolting the TB and bolting it back up with a new seal and torquing to spec.

 

[waypoint]

By seal, do you mean the gasket between the throttle body assembly and the motor?

The gasket between the TB and intake manifold.

 

[jcampo788]

That is what I figured. Now I just need to figure out the part number.

The gasket between the TB and intake manifold.

 

[waypoint]

That is what I figured. Now I just need to figure out the part number.

If you have a NAPA nearby: Attention Required! | Cloudflare

 

[Hunter61]

If your going to remove the throttle body for cleaning you may as well clean the Idle Air Control Valve body too.

https://www.youtube.com/watch?v=VOUB1UiDkKc

 

[BlackWorksInc]

Greetings all!

I have a slight hard start occassionally on my T4R, V6, 318K.

I have decided that it is likely the throttle body, considering when I replaced the battery last weekend it had a hard idle when I started it post new-battery install.

I saw a video on Youtube where someone cleaned the throttle body and blade without removing it. I then saw the tutorial on here where it was removed (four bolts).

Can you clean the throttle body without removal?

Yeah you can clean it without removing it; just make sure the vehicle is completely off when you do this. IF you try to move the throttle blade with the vehicle on you can at the very least set codes, at worst damage the throttle body.

We use either throttle body cleaner on a rag/brush or non-chlorinated brake clean. You want to focus mainly on the ring that the throttle plate contacts and the edges of the throttle blade, that's what's going to restrict air-flow; cleaning anything else is just for those that have an obsession with cleanliness (guilty.)

If your going to remove the throttle body for cleaning you may as well clean the Idle Air Control Valve body too.

https://www.youtube.com/watch?v=VOUB1UiDkKc

Toyota doesn't use an IAC on their electronically controlled throttle bodies.

 

[Drcoffee]

The throttle body gasket is reusable. Leave the coolant hoses attached, remove the 4 bolts holding it to the intake. Then spray carb cleaner on a soft rag, spray the butterfly plate and wipe it all clean. As mentioned above, keys out of the ignition. Gently open the throttle plate and clean the edges of the plate. Bolt it all together and your done.

But it might not help. Fuel pumps generally last 180,000 miles. You, like me at 223,000 miles are on borrowed time. Slow to fire up is most likely a dying fuel pump. Not only is mine a little slow to fire, my long term fuel trims are adding fuel under load. Meaning the pump isnt delivering enough pressure causing a lean condition.

 

[Hunter61]

Toyota doesn't use an IAC on their electronically controlled throttle bodies.

If that's the case then it's something to scratch off my to do list. I assumed they had one without looking first.

 

[BlackWorksInc]

If that's the case then it's something to scratch off my to do list. I assumed they had one without looking first.

The idle is adjusted by the ECM with electronic throttle bodies. They set a default amount that the throttle blade will sit open at idle to act as an IAC. This is why if the throttle body is dirty and you reset the memory (like disconnecting the battery) the vehicle will idle poorly for a bit while it tries to relearn stable idle. If the throttle body is dirty enough it'll just end up having a rough idle (it can only adjust that idle setting so much.)

 

[jlaw904]

Just out of curiousity, with that mileage, how often/when did you change transmission fluid? I've seen some conflicting arguments but want to hit that 300k club. I bought at 176k but not sure if it's ever been done.

 

[waypoint]

The throttle body gasket is reusable.

Sure, but at high mileage and repeated heat cycles it's hardened and compressed...risk of it not sealing properly vs. $5 gasket isn't worth skipping in my experience.

 

[Drcoffee]

Sure, but at high mileage and repeated heat cycles it's hardened and compressed...risk of it not sealing properly vs. $5 gasket isn't worth skipping in my experience.

Help me understand where the “high heat” cycles are coming from. Its a foot off the front of the motor with fresh cool air inside and a radiator fan blowing over 100% of the time the engine is running.

Just re-use it.

BTW I just had to remove mine to do fuel injectors. After 220,000 miles on an ‘07, it was just fine.

 

[waypoint]

I wrote:

Sure, but at high mileage and repeated heat cycles it's hardened and compressed...

You wrote:

Help me understand where the “high heat” cycles are coming from.

Have somebody help you understand reading.