Well I was having trouble with a low idle and wanted to replace my tb because of it. Some members on the forum suggested otherwise and while it didn't help with my low idle I have heard it helping rough idles and codes involving the throttle body.
*DISCLAIMER* This is what is necessary for tb cleaning on an 04-08 f150 model 5.4 3v. Other vehicles may differ but the idea is the same
Here's what you will need for this project
1 socket wrench
1 can of throttle body cleaner ( I used CRC brand)
DO NOT USE CARB CLEANER ON ANY TB, IT WILL DESTROY THE TEFLON COATING ON THE BUTTERFLY VALVE
1 Can of MAF sensor cleaner (CRC brand)
t20 security screw bit
1 old toothbrush (You can use other brushes just don't use ones with metal in them)
optional- air compressor
patience and spare time- about 40 minutes if you're good at this kind of thing
1: Pop your hood and use the 8mm socket and wrench to loosen and remove the negative battery cable
2.Next remove the 10mm socket holding on the tube for your air intake
3. Remove Air filter, Air Filter Tray, and Air Filter housing by loosening the 4 bolts and the base of it with your 10mm socket and wrench. *NOTE* In the filter housing you will see something that plugs in using 2 t20 torx screws. If you wish to only clean your MAF this is where it it. Simply disconnect the electrical wires and clean the MAF as outlined in the later steps
4. On the side of the housing there are two connections. One is for the mass aif flow sensor or MAF and the other is some kind of tubing on the passenger side of the housing. Remove the MAF using the t20 security screws and by unclamping the electrical connectors. The tubing on the passenger side has a small green security latch that just needs to be push down in order to release the tubing.
5. Your engine bay should look like this now
6. Again using the 10mm socket and wrench loosen the four bolts that are holding your throttle body on. Also make sure to loosen the throttle body position sensor and Idle Air control connectors that are secured to the throttle body. Your removed throttle body should look like this
Your engine bay should now look like this
*NOTE* Place a clean rag over the opening that is exposed in your engine bay to avoid anything falling in. If you feel the your engine bay is a little dirty you can use an air compressor to blow out some of the dirt that has collected in some of the folds BUT MAKE SURE that while you're blowing the crap out that you hold the rag securely over the opening to avoid any dirt of foreign particles from entering the engine.
7. Using your TB cleaner spray lightly inside the throttle body, making sure to move the valve back and forth to let the cleaning agent work. Now take your toothbrush and/or rag and clean out/off all of the sludge.
*NOTE* make sure not to spray any of the cleaner into the electrical connections for the IAC or TBPS.
When its clean the TB should look similar to this
8. Although I have no pictures, cleaning the MAF is just as simple. Make sure it is disconnected while cleaning it and that you do NOT touch any of the wires as this will cause premature failure and you will have to purchase a new maf ($130+ for this truck)
Following the directions I did 15 bursts of the MAF cleaner by CRC onto my MAF sensor. After that I took the air compressor and blew out the Sensor in order to ensure that it was dry (don't plug it in until it is completely dry as that can also cause failure)
9. Install everything in the reverse order and start your vehicle. With mine it took a little extra cranking compared to usual on the first 2 starts so don't worry if yours does the same.
10. Start the truck, this may take more cranking than normal because a little of the cleaner will get into the engine. This is normal and nothing to worry about. Crank the engine as long as you normally do, if it doesn't start quit cranking, wait a few seconds and start again. Once started.....
11. Follow the owners manual procedure for helping your vehicle's computers to relearn how to operate. for f150's the steps are as follows
a. Turn on your vehicle and allow to reach normal operating temperature
b. let idle with radio and ac off for one minute
c. while still idling turn ac on and let idle for one more minute.
d. drive the vehicle at different speeds for a minimum of 10 miles in order to help the ECU and PCM relearn your driving habits.