Accessing & Cleaning the Throttle Body (Pics!)

[erw38]

*The below "how to" guide is dedicated to Steven.*

How to access the Throttle Body in order to clean it:

Difficulty: Beginner

Step 1: Identify the parts you are dealing with.



Step 2: Where do I begin?



Unscrew the clamp the holds the air tube onto the air box.

Step 3: Lift up the end of the tube (a flat screwdriver might help in doing this),



Step 4: Unscrew the other end of the tube and then pull it off.



Step 5: After you pull off the tube you will discover the MAF sensor.



Step 6: Unscrew the screws that hold the MAF sensor to the throttle body. (Do NOT unplug the electrical connection when you take the MAF sensor off. Leave it connected and set the MAF aside.) (Do not drop any of the 3 screws!)



Step 7: Here is a picture of what you will see when you get the MAF off. Notice that you can see the other two screw holes.



Step 7a: Here are more parts identified.



Spray all exposed surfaces with throttle body (including the butterfly valve) liberally with THROTTLE BODY CLEANER (do NOT use Carb cleaner). (Make sure the little red straw that attaches to the can does not fly off into the internal engine) After spraying the surfaces, go inside and have a drink in order to let the spray work it's magic. Come back about 10-15 minutes later and start scrubbing the surfaces with a soft bristled tooth brush and wipe clean with a terry cloth rag until the TB shines.

Step 8: Reattach everything starting with the MAF sensor and then the air tube.



Step 9: Drive happy!*

* Note - when you start your car, it may idle rough for a few minutes while it is burning the TB spray off. This is very normal, so don't panic!

[BuccaneersFan]

Great write up!

Why can't you use carb cleaner instead of throttle body cleaner, will it hurt something?

[Roop]

nice post! i was just having horrible thoughts about what might happen if that straw gets blown in there. gasp. what would happen? i don't think i'm going to use the straw ever again.

for those of you who don't know, my 98 never had it's throttle body clean. it had problems idling so the mechanic that "fixed" the problem just jacked the idle screw without cleaning the TB. after i cleaned the TB my car was idling at 1200rpm. i lowered the screw and it has run smooth with better fuel economy ever since.

i would recommend atleased looking at it when you change your air filter. it should be shiney metalic. if it's black, it's dirty. mine had a thick blad film all around.

oh another note about this: when using throttle body cleaner: put a rag directly below the TB. it's flammable so you don't want it spilling everywhere. the TB is angled so liquids flow out of it.

[SupaStealth]

one thing though, be carefull not to have the butterfly open for too long, i had a vice grips holding mine open so i could clean it, and now the spring doesn't close the throttle all the way, which really is a pain, going to a stop light while idling at 1300rpm definitely isn't good for the torque converter. thought i'd save somebody with that coment

[erw38]

buccaneersfan said:

Great write up!

Why can't you use carb cleaner instead of throttle body cleaner, will it hurt something?

I believe carb cleaner is more "chemically potent" and will eat through the thim film that the TB has that protects it.

roop said:

i lowered the screw and it has run smooth with better fuel economy ever since.

What screw did you lower?

[stevensolds]

Supa you might be looking at a rebuild if yours idles at 1300rpm all the time. Its like brake-torqueing, lol. Although you probably get up and going faster.

Thanks so much Elan i really appreciate it. I hope i dont fudge nothing up. What would happen if i lost a screw, lol.

Hey Elan did you clean your dirty throttle body during this whole thing? It looks dirty in one pic but clean in the one before it?.

[erw38]

Thanks to everyone on the writeup comments. I hope I did it correctly. If anyone has and tips and/or tricks for the cleaning or whatever (other then those already mentioned), please don't hesitate to say them.

stevenolds said:

Hey Elan did you clean your dirty throttle body during this whole thing? It looks dirty in one pic but clean in the one before it?.

That is because in the clean pic, the butterfly vave is closed. In the dirty pic, the valve is open. I did not get to clean it because after I took everything apart, I was not able to find the throttle body sray anywhere! As luck would have it though, I walked inside after putting everything back together and say the TB spray sitting right there on the shelf! So, I will take it apart another day. When I do that, I will do the EGR valve too and show you how easy it is to clean that too. ;D

[scottydl]

Awesome!! Now I *really* have no excuse not to do this. As soon as the outdoor temp isn't pushing 95-100 degrees (with the heat index) like it has been lately...

[SupaStealth]

stevensolds said:

Supa you might be looking at a rebuild if yours idles at 1300rpm all the time. Its like brake-torqueing, lol. Although you probably get up and going faster.

i didn't do it by choice, i don't think anyone would, especially with me havin' no exhaust idling that high with a cop behind, yeah.. no good. and like i said, i'm sure it's not good for the torque converter. i'm tryin' to find a way to fix the spring by puttin' another one on or replacing it with a new spring.

[BuccaneersFan]

erw38 said:

buccaneersfan said:

Great write up!

Why can't you use carb cleaner instead of throttle body cleaner, will it hurt something?

I believe carb cleaner is more "chemically potent" and will eat through the thim film that the TB has that protects it.

The reason I asked is because I just cleaned mine a few days ago and I used carb cleaner. ;D I haven't had any problems (yet), next time I will use throttle body cleaner.

Anyway the back side of the butterfly valve had about a 16th of an inch of black gunk stuck to it. It was also starting to stick when I pushed the gas pedal, but now it works great.

[oldsauroraman1]

The fellows at our local parts store sold me the TB Cleaner and stated that it is milder than the carb cleaner and supposed to be "safer" for all of the sensors etc.

[Letitroll98]

Sweet. Nice post.

[erw38]

letitroll98 said:

Sweet. Nice post.

Thank You Sir.

[stevensolds]

Hey elan..i got the TB spray and engine degreaser spray today also. for the degreaser though, it says to hose down after you let it soak in..! What shold i cover up before i let water touch the engine? The thought of water..uh, frightens me a bit, especailly if it gets in the PCM or something electronic.

[erw38]

I have never washed my engine, so I don't know. I would assume that you should cover the coils, alternatior (do know if you can even see the alternator on this car) the MAF area, and possibly the PCM (again I don't know where that is). But I would ask 40 or someone else that has done it with success before you attempt it.

[scottydl]

stevensolds said:

Hey elan..i got the TB spray and engine degreaser spray today also. for the degreaser though, it says to hose down after you let it soak in..! What shold i cover up before i let water touch the engine? The thought of water..uh, frightens me a bit, especailly if it gets in the PCM or something electronic.

Also, when you hose it down make sure you are parked over gravel, dirt, or on the street... otherwise the sludgy mess that rinses off will make an AWFUL mess on the driveway! (I know from experience unfortunately )

[stevensolds]

best to wait til engine cools down to do TB?

[erw38]

stevensolds said:

best to wait til engine cools down to do TB?

Unless you feel like burning yourself ;D

[BuccaneersFan]

Steven, I cleaned my engine a couple of months ago and you can get the engine compartment pretty wet without any problems. I wouldn't purposely spray the hose right at the electrical parts but if they get wet its no big deal. In fact I got the coil pack pretty wet and had no problems at all. I used a big soft bristle brush to scrub down certain parts that needed it. Came out real good. I have some before and after pics that I'll post if I can find them.

[stevensolds]

Cool, yeah i woudl like to see the pics. I figured evertyhing would have to be sealed up pretty good anyway, lol.

Guess what Elan, i did it today..hehe. It idles a lot smoother, thats for sure. You wouldnt believe how gummed up it was..i shouldve taken pics. There was so much black stuff in there that I had to repeat the process 3 times. Took me about an hour and a half. It doesnt do that "jumping" or "searching" rpms at idle anymore at least which I am happy for. Hopefully it will yield me better mileage over time too.

At least i feel comfortable now that I could do it.

[erw38]

Great to hear that Steven. I guess a little confidence goes a long way! Now that you have "graduated," what are you going to try next? Brakes? Oil change? The possibilities are endless.

I am so proud. You just brought a tear to my eye.

[gearhead]

is there a MAF sensor that you can purchase that will bump up the horses a little? How hard is it to get to Screw 3?

[erw38]

I don't know of any MAF you can get to bump up the horses. I don't believe one exists for this car. As for screw 3, it is not difficult to get to. Just feel arould by hand and you will be fine, but DO NOT drop the screw. You may not find it.

One tool that I love is a telescoping rod that has a litle magnet on the tip. It is great for reaching the screws and tools that you do,unfortunately, drop into the engine.

[BuccaneersFan]

erw38 said:

One tool that I love is a telescoping rod that has a litle magnet on the tip. It is great for reaching the screws and tools that you do,unfortunately, drop into the engine.

When I cleaned my throttle body I dropped the #3 screw along with the head to my socket wrench, thank god for the telescoping tool. ;D

[erw38]

buccaneersfan said:

erw38 said:

One tool that I love is a telescoping rod that has a litle magnet on the tip. It is great for reaching the screws and tools that you do,unfortunately, drop into the engine.

When I cleaned my throttle body I dropped the #3 screw along with the head to my socket wrench, thank god for the telescoping tool. ;D

You would never guess, but I have done that many times before.

[stevensolds]

I wouldve gone crazy. One thing though...it may just be that mine is a 95, I did not have that extra filter thing, nor did i have to remove 3 screws. Just the hose going into the MAF. There was a thing above that I could remove, but i could still access the TB. i took the lazier way and bent over the whole time scrubbing it with 4 different old toothbrushes.

I didnt have that white "filter" -like element that elan has in that pic above. Anyone else with a 95 notice this? If other ppl with 95s here have it, must be something else missing on the car.

[95mushroom]

stevensolds said:

I wouldve gone crazy. One thing though...it may just be that mine is a 95, I did not have that extra filter thing, nor did i have to remove 3 screws. Just the hose going into the MAF. There was a thing above that I could remove, but i could still access the TB. i took the lazier way and bent over the whole time scrubbing it with 4 different old toothbrushes.

I didnt have that white "filter" -like element that elan has in that pic above. Anyone else with a 95 notice this? If other ppl with 95s here have it, must be something else missing on the car.

I think 95's don't have a MAF altogether. I don't have one.

[scottydl]

I successfully completed this maintenance procedure this past weekend! Thanks to all of the warnings in this thread, I was very careful and managed to NOT drop any of the TB screws when removing the MAF housing. Here are some photos and observations of my own, FWIW:

With the hose and MAF housing removed, here's my Throttle Body and the toothbrush I used for cleaning BEFORE:



I had to spray about half a can of TB cleaner into the hole, and placed an old wadded-up T-shirt under the hole. Even with that much cleaning solution, it was hard to make a lot of progress with a toothbrush. The grime inside my TB was like burned, baked-on, black tar... and it was thick! I had more luck using a piece of cotton fabric (cut off sleeve from another old shirt) soaked in cleaner, holding it with a pair of pliers and scrubbing above and below the butterfly valve.



And the AFTER pics... the toothbrush, the rag, and the MUCH cleaner throttle body. The light brown residue shows where the grime was dribbling out from every part of the TB opening. Notice the butterfly valve is silver now! Even these pics don't do it justice... it's a difficult process to photograph.



I also blasted my MAF screen clean with some compressed air-in-a-can while it was removed. For a TRUE throttle body cleaning, you'd probably need to remove it completely so it could be cleaned from both sides. I know Bonneville owners who have done this, but I don't know how much harder it would be on our engines.

I highly recommended this procedure, as others have. My accelerator doesn't stick anymore, and the increase in lower-end throttle response was VERY surprising. She runs silky smooth and really jumps off the line quicker, with little effort from my right foot!

[stevensolds]

Mine was a lot worse than that. I didnt have any screws to remove at least either. Maybe yours was cleaned before?

I was afraid to put too much TB spray in there. Maybe I will do the procedure again. Also there was a lot of gritty gunk on the bottom of the enclosure to sweep out. I figured if id have left it in there it would have went into the engine.

[95mushroom]

Yea, I completely removed mine to clean it. I would suggest this to everyone as the mounting plate behind the TB is also covered in carbon. It wasn't too hard, the throttle linkage was probably the trickiest. I would post the procedure, but that was well over 1 year, probably 2.

Mine was also horrible. My air intake tube is badly warped at the connection at the air box. Either the previous owner or mechcanic tightened the hose clamp with a pair of pliers so tight it bent the hose clamp area where you're suppose to tighten it by hand and destroyed the tube. Sometimes I wonder why I bought this car. So needless to say the TB and TB plate was really dirty, around 1/8" thick. Even the back of the butterfly was covered. Not sure you guys got everything as I had to use a chisel and flathead to chip some of crud off. Also, all the little air passages into and out of the TB was clogged.