Throttle body cleaning and relearning PSA/How to

Recently, I had some issue with starting and a bit of rough running with rather sluggish throttle response. To remedy this, I replaced the plugs (don't go cheap on these old models!) and cleaned and relearned the throttle.

I've read a lot on cleaning and relearning the throttle and thought I'd share what I've found the be the easiest method:

Cleaning:
- Remove the intake from the throttle body
- Only need a 10mm to loosen the clamp holding it on, then just pull it up and out of the way
- Grab some throttle body cleaner, a cheap toothbrush an some towels
- Once the intake is out of the way, spray come cleaner on the toothbrush - easier and less messy than spraying straight into the body.
- Manually move the butterfly valve and scrub anything that looks dirty
- Particularly the edges of the value that meet the body, as well as the portions of the body where the valve meets.
- It's a bit tight, but try to get as close to the center/pivot (I'm sure there's a name for it, but I don't know it) to clear as much gunk as possible
- Wipe away as much excessive as you can

Relearning:
- Turn the ignition on to ACC (accessory)
- Slowly press the throttle from 0 - 100% over roughly 5 seconds or so, holding 100% for a few seconds
- Slowly release back to 0 over 5 seconds or so
- Rinse and repeat at least 3 times, preferably 5+
- Turn the truck off and let it sit for 30-60 seconds
- Turn the truck on and test out the throttle
- Drive it around a bit and enjoy a much smoother, more responsive throttle

 

Adding to this, a small correction for "Relearning" per this member's experience (link), to put the key to the ON position (but with engine off) and not the ACC position:

"I am happy to report the relearn process definitely works. My throttle response is now linear, there is no longer a "dead" spot and then a surge of power! The only amendment I will make to the process is the step where it instructs to turn the ignition to ACC. That does not work. I ended up turning the ignition to the ON position and going through the process as written from there. Which makes sense. ACC is only going to power radio and accessories. The ON position is going to power everything. I sincerely appreciate your help, and the wealth of knowledge in this forum. I'm getting better at navigating around here, but your kind guidance is very much appreciated!"
​

I can't say for sure which is valid by the FSM, I've never looked. But if you're reading this because you have a jumpy / sensitive / aggressive pedal, and you don't want to make the mistake of getting a product like Pedal Commander (which has been catastrophic for others), if ACC key position doesn't work for you, try repeating the process with the key in the ON position.

And on the "Cleaning" portion, be careful to not let the throttle plate/butterfly slam shut.

 

Thank you for the addition(s) shifty! I don't recall anymore, but it's possible that I meant to say the "On" position, but conflated it with "well the engine isn't on, must be ACC" lol. Nevertheless, thank you for the valuable edit!

 

The accelerator relearn process on my 06 tundra worked! I was so aggravated with my jumpy/deadspot pedal (felt like it was surging) that I was considering buying one of those pedal commanders or bank monster pedals until I read this thread. Thank you for posting this!

 

Welcome to the forum! I think this thread is linked from the "nuisances" section of this thread for gas pedal issues. You may find other tips there that'll make your ownership experience better.

 

I appreciate the timely response but i read not to manually move the throttle plate as it will damage the position memory...any truth to that?and how can i clean behind trhe plate without damaging it?

 

I haven't personally experienced any issue with moving the throttle plate, sounds like BS. If it doesn't skip teeth, how would it?

How to clean behind the plate? Remove the TB. But let's be realistic here: The major issue with TB cleanliness is buildup where the plate meets the wall of the TB. Secondarily, buildup on the wall of the TB itself. You (A) don't need to remove the TB to clean up those two major issues and (B) As long as you're not forcefully opening/slamming the TB plate, or wedging anything forcefully in there, it shouldn't be an issue.

I've been cleaning TBs my whole life, across at least 2-3 dozen cars I've owned or had as projects at this point (maybe more). I've never had an issue on any vehicle (GM, Toyota, Honda, VW primarily) while cleaning the TB. I always keep a couple of fundamentals in mind:

1. Always disconnect the negative battery cable when working, and leave off for at least 10 minutes to force an ECU re-learn after
2. Never wedge or force open the butterfly/plate
3. ALWAYS use the appropriate cleaner, i.e. a can that is specifically labeled "Throttle Body Cleaner", and I think CRC makes the most reliably-good products on the market
4. ALWAYS clean the MAF at the same time with an appropriate cleaner, i.e. a can that is specifically labeled "MAF Cleaner", and I again prefer CRC's products
5. Always use a little rubber-safe lubricant around the TB opening where the air intake mates with it to avoid it getting stuck
6. Expect potential rough running at first, after the cleaning, take a short test drive after to help the ECU re-map

Obviously, everyone should do what they're comfortable with. How I handle things may not be the way others do, and I don't take any responsibility for what you choose. I'm not a certified mechanic. I'm an engineer by trade, so anything I type on here is colored by that lense.

 

No problem manually opening the throttle plate. Don’t let it slam shut. Don’t use a screwdriver or anything sharp to hold it that may gouge or scratch it.

 

I straight up unbolted my TB and went to town with MAF cleaner and fresh rag. Could probably bust out the plastic bristle brush but the rag did fine.

sputtered on first start up, had a rough idle for like 30seconds then went back to normal. Next start was perfectly fine.