MAF Sensor and Throttle Body Cleaning

[1000MPH]

I cleaned my MAF sensor and throttle body today so thought I’d post some pics.
I bought these 4oz cans at Walmart for about $8.
CRC Mass Air Flow & Throttle Body Single-Use Cleaner Twin Pack Kit - Walmart.com - Walmart.com
I didn’t use nearly as much as some of the guys on YouTube use, not even 1/2 of each can.
First off, I pulled the engine cover, set it aside, then located the MAF and throttle body. Damn easy to get to, I love this truck!



Edit: Adding part numbers and links to the Toyota Parts Website:
Fuel Injection Throttle Body 2203031060 List Price: $403.83
2203031060 - Fuel Injection Throttle Body - Genuine Toyota Part
Mass Air Flow Sensor 222040V010 List Price: $153.34
222040V010 - Mass Air Flow Sensor. Meter, Intake Air Flow - Genuine Toyota Part

 

[1000MPH]

Next I removed the intake assembly. There are a couple things to remove first:
Loosen the big screw clamps.
Remove the vacuum hose.
Remove the harness clamp.
Remove the 10mm bolt.
Remove this 1” hose as well.

 

[1000MPH]

Here’s a pic with the intake removed.
My 10 year old truck is pretty clean but the intake still had plenty of dust on the outside and in the crevices. I will clean this up too.

 

[1000MPH]

110,000 miles and the throttle body does not look bad at all. I tend to replace my air filter every one or two years depending on how often I’m using the truck in dusty conditions. When off-road I like to avoid eating other people’s dust and it looks like it’s paid off.
Remove the connector by squeezing the little tab and pulling. It comes off pretty easily. I pulled back the hose clamps at this time too. Then remove the 4 10mm bolts.

 

[1000MPH]

After removing the bolts, I can pull the throttle body away and see the backside. Now I see that it can use some cleaning.
At this point, I removed the two coolant hoses and plugged them with rubber stoppers. Only a few drops of coolant came out onto the towel I put under them.

 

[1000MPH]

Next I took the throttle body outside and cleaned it up with the CRC throttle body spray and clean towels.

Note: FSM states: Do not spray TB cleaner directly on TB, use a cloth towel soaked in cleaner.

You can open the spring loaded butterfly with your fingers but try to be gentle with it, it’s attached to a motor that controls the throttle (drive by wire).
Do not try to take the butterfly out, I’m pretty sure those screws are permanent anyways. Back in my motorcycle days I remember a friend that locked up his Honda CB360 because his motor ingested a carb butterfly screw that worked itself loose. Here are a couple before and after pics.

 

[1000MPH]

After cleaning, I reinstalled the throttle body and took out the MAF sensor.
To remove the connector, make sure you fully squeeze the clip and it will come off with no issue.
Then remove the two Phillips head screws. Don’t drop them.
The MAF was pretty clean as well, I could not see any dust on it at all but shot it with the CRC MAF cleaner.
After making sure it was dry, I reinstalled the MAF and double checked all of the clamps, hoses, and electrical connectors.
I started up the engine and looked for any trouble codes. None. The YouTube vids warn of a high idle after cleaning but I didn’t really see that either.
Done for another 5-10 years.

A big thanks to Jivewalker for his write up, his might be even better.
Throttle body / MAF sensor cleaning

 

[1000MPH]

Throttle Body DTC charts.

 

[vipers28]

[MENTION=53327]1000MPH[/MENTION] Sorry for the dumb question but this looks relatively simple DIY project. Is there any risk or issues or chance of f'ing up the throttle body if you DIY it? Can fault codes be triggered? Thanks

 

[1000MPH]

There’s always a chance to throw a code for something. Any code during this maintenance job can probably be cleared by disconnecting the positive battery terminal if you don’t have a code reader or TechStream.
I added those codes above because we couldn’t add any attachments in the recent thread on throttle body issues. Found here…

https://www.toyota-4runner.org/5th-gen-t4rs/298780-t4r-went-into-“limp-mode”.html

This job is pretty simple. The important points would be:
Do not touch the MAF wires inside the sensor and use the correct cleaner.
Don’t use a brush, paper towels, or rags on this part either, just keep spraying the crap out of it if it’s really dirty. Mine was pretty clean to begin with.
Be sure to let the MAF sensor dry before installing.
Use caution when disconnecting and reconnecting the vacuum, coolant, PCV, hoses, connectors, clamps.
I’ve seen a broken connector on someone’s TB in a how-to vid.
Don’t drop anything downstream of the TB. I wouldn’t try to clean in there either.
You can use rags and paper towels on the TB but use care when opening the butterfly. I think I’ve seen someone say don’t open it at all. Seems a bit dramatic.

There’s a bunch of pretty good vids on YouTube from Toyota mechanics and DIYers I recommend you check out first.

 

[1000MPH]

Just saw this YouTube vid from the Car Care Nut on Throttle Body function and cleaning.
Should you clean your Throttle Body and How to clean it on Toyotas - YouTube

 

[Jeremy556]

Cleaned my throttle body Friday for the first time at just under 300k miles. It was a little nasty. Stupid PCV system

 

[03_4x4Runner]

Just saw this YouTube vid from the Car Care Nut on Throttle Body function and cleaning.
Should you clean your Throttle Body and How to clean it on Toyotas - YouTube

I had never heard of that YouTube Car Care Nut before but I checked out more of his videos. He has a lot of cool 4runner information videos on there.

 

[1000MPH]

It’s really easy to remove the TB completely but I guess the pros don’t waste their time. The vid I just posted is pretty much the opposite of Petr on the Toyota Maintenance YouTube channel. He uses a ton of TB cleaner.
How to clean throttle body on Toyota Sequoia - YouTube

 

[1000MPH]

It’s been three years and 25k miles since the last cleaning so I thought I would do it again to assess a good interval…and I’m already doing a bunch of other maintenance and cleaning chores.
The MAF was perfectly clean visually and the TB was clean on the frontside with a little staining on the backside.
I will probably increase the interval to 4-5 years and about 35-40k miles.
I replaced the air filter at this time as well.
I did see what looks like some minor rodent damage on some wire sleeve material for the fuel system. I didn’t look like chafing damage.
I put some electrical tape over the damage and will keep an eye on it.
While I had the cover and intake off I vacuumed up a bunch of sand between the cylinders too. The intake was fully protected while I did this.

 

[Rocko9999]

Is it mandatory to clean the MAF when cleaning the TB?

 

[1000MPH]

No. They’re commonly done at the same time since they’re both part of the intake.

 

[T4Rgarage]

Did you notice an improvement in throttle response, idle, fuel economy?
I'm going to clean my MAF sensor tomorrow

 

[1000MPH]

I didn’t either time since everything was pretty clean to begin with. I didn’t have the high idle or anything like that. Would be hard to improve my mileage if you look at my Fuelly below.