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Throttle Body Service????


Charter Member
Full Member
Jan 30, 2002
Left Coast
Took my Av in for some Routine Maint. at my local Dealer here in Huntington Beach, CA (Delillo Chevrolet).
I have never had the 6 month or 1 year service done so I tell the guy I would like to catch up. He tells me he can do a 18K mile maint which would include "cleaning" the Throttlebody. They also did oil, all fluids, inspec brakes, rotate tires etc...
The bill came to $260.
Is Throttlebody cleaning a legitimate scheduled requirement? Or is this guy blowing smoke?

Thanks :9:
I just looked thru my owners manuel, for my 2002 1500 5.3L and it said to replace the fuel filter at 30K & 60K but never mentioned anything about cleaning the throttle body.
I haven't heard of this as part of any maintenance schedule either, but every throttle body I've looked down into has been full of soot and carbon buildup. So maybe it's not a bad idea?

I did find something that may be related under Periodic Maintenance.

"Throttle System Inspection - Inspect the throttle system for interference or binding,
and for damaged or missing parts. Replace parts as
needed. Replace any components that have high effort
or excessive wear. Do not lubricate accelerator and
cruise control cables."

It says it should be "checked" twice a year.
From the Dec '02 GM Tech Link:
"The Throttle Body Cleaner is packaged in a spray can and is used to clean the throttle body and lubricate the throttle plate. It also cleans the idle air control bypass. This product is toluene-free and includes an ester oil lubricant."

I think it's worth doing every year. Like brmiller said they get pretty nasty so for me personally, i do it. But it's also free to me. (Work) As far as your question..."Is Throttlebody cleaning a legitimate scheduled requirement? Or is this guy blowing smoke?

Depends on who you ask. In the owner's manual, no. In a service advisors schedule, usually. It all comes down to how well you want to take care of your AV. If you follow thw owner's manual, you will stay on the good side in most cases. If you go past the manual and go for maximum preventitive maintence based on visual inspection and/or mileage based service menus then you are just taking extra steps to insure the long life of your AV.

One last thing did he sell you just a throttle body cleaner or a 3 Step Maintenance Fuel Induction Service ?
It's a very good idea to clean the throttle body about once a year, however you won't find it in the owner's manual. The throttle body may never give you a problem or it just may. I had a Villager throttle body that stuck because of carbon buildup...not good.
I think the dealer should have looked at it first, determined if there was a problem, and then ask you if you wanted it cleaned. It could have been fine.
I found out the GM is having problems this their GMT-800 series trucks' (99 pickups & the Tahoe/AV/EXT/etc..) throttle bodies sticking open. ?The US government, I forget the agency's name, is investigating and keeping an eye on it. ?NO RECALLS YET.

What's happening is that the butterfly valve is sticking in the open position and the driver needs to tap the accelator to free it up. ?When this is done, the truck "lurches" ahead (no kidding dumby, you get tapped the gas) and the driver "can" lose control.

So, I'd recommend cleaning you TB at least once a year. ?
Oh yeah, I'm thinking this is something a person can do in the driveway. I "think" it's a matter of pulling off the air intake in front of the throttle body and shoting in some cleaner. I'm not sure becasue I haven't done my yet.

If anybody has done this, can you please post to confirm or correct?

I'm planning on making this one of my normal Spring tasks, along with the fuel filter, PCV valve, and air filter.
Thanks for all the replies! Sounds like it was a good suggestion by the service guy!

No -The service writer did not sell me any "cleaning" kit. They just performed the service.

Thanks again for the response.
Brad in HB
I have cleaned mine 2X now. I have 26000 mi.

They get dirty and yes, will get sticky. It is a very simple procedure as mentioned above and can be done at home. The whole procedure should only take about 1 hour from removal to reinstall.

You can shoot the cleaner through the front with the throttle closed and wipe up the residue with a rag but the preffered more thorough method is to remove the TB.
I did this service today. You just have to remove 2 hose clamps and remove the plastic air box. Put a rag below the TB and spray away. Open and close the flap and spray all around. Start the Av and repeat a second time. The only problem I had is I got a service engine light come on. I removed the battery cable for about 10 minutes and put everything back together and started it up. I still had a SE light on. Once I turn on the Av for the 3 time my light went out.
I can tell you as a tech that performs this service daily. Remove the air inlet hose and spray the throttle plate with the throttle open untill any black build up is gone - you can use Choke and carb cleaner from any parts house. You may notice the truck does not want to start right away if you use alot - just hold the pedal down and it will start. Be sure to reinstall the air intake hose first as the computer needs info from the mass air flow sensor. It may run rough for a moment but let the engine run until it smooths.
This is a good and necessary service to perform from time to time.
Note - Never scubb or scrape the inside of the throttle bore with anything. If you want to wipe it do so with a soft lint free rag. (spaying should be sufficient)
i will be cleaning mine today when i change my oil. i normally clean the one on my wives truck. this will be the first time on the AV. :B:
Be dam sure that the can you use says FOR THROTTLE BODY injection.

Regular carb cleaner is too harsh and will damage the clear coating on the inside of the body.
did mine the other day. it was too easy. so easy i did it in the dark. i got my Snap-on light out later to make sure i reconnected everything correctly. yep! all done. :B:
I haven't cleaned the throttle body on avalanche yet but I just cleaned it on my 00' Silverado for the first time and it was nasty. I used Berrymans spray carb and choke cleaner and it did a great job. Just removed the air intake hose, open up the throttle plate and used the whole can to get it clean. This is now my part of my 10,000 mile maintenance. After the cleaning the throttle response was much better. It smoked like crazy when I started it after the cleaning but soon cleared up. Very easy job and well worth doing often. :9:
This is somthing I have done on my 94 Silverado several times and I believe that's why it's still runs like a champ after 156k miles.
In addition, you may want to have your fuel injectors cleaned. Using fuel injector cleaner in the gas is ok, but taking your AV in for a closed loop clean is highly recommended. It's done one of two ways. It can be done from underneath using the fuel line or from under the hood using the fuel hoses behind the TB. They hook all the lines up in a loop with a pressure cleaner and detergent that will clean your injector nozzles. It's important that you change your fuel filter afterwards. This service should run around $60. It may be a bit more if you replace the filter.
Most of the grime in Fuel injectors comes when you run all the way to the bottom of your gas tank. If there is anything in your gas tank it will settle at the bottom and get sucked in when you run your tank close to empty( 1-2 gallons left). This is why I do my best to fill up when I have a 1/4 of a tank left.
You just never know when you are at the pump if you are sucking from the bottom of that tank either. I have read story's of what happens to gas before it gets to your tank, and you can never be to careful.
Anytime you do cleaning to your fuel system, wheter it's an additive to your gas tank, or cleaning your injectors, you should also take a look at your spark plugs and give them a good cleaning. It all adds up!!!

I recommend doing this when you do a tune-up:

1. Clean the Throttle Body
2. Clean injectors
3. Replace filter
4. Clean or Change Spark Plugs

CT :B:
My neighbor just came over to show me a can of throttle body cleaner made by Gunk. The instructions are to have the engine running, and spray into the TB for 10 seconds, wait 10 seconds, etc. till can is empty. He had just done his truck, and his 2 boys trucks. He said a lot of black carbon came out the exhaust for about 3/4 of the can, then cleared up. He said all trucks now seem to have a lot more pep.
I would worry about these sprays ruining the O2 sensor and Catylitic convertors.......

I mean how dirty does your TB get.....

Mine never looks bad.......even after 32K......

I dunno.......guess it is me...

I'm not sure how they affect the catalytic converter but I don't see any problems with the O2 sensor. I have noticed a big difference in the throttle response and performance though. I didn't look real dirty when I took of the intake hose but if you look around the throttle plate there's a nasty, gummy film that forms around the whole bore. When I open the throttle plate up, man it was nasty. Blacker than pitch!! :D: I then put in a can of Berryman's B12 in the tank just for added cleaning. Seems to be doing great. I try to put in one can of Berryman's B12 (in the metal can) every 3rd fill up. :love:
I have a 1992 Grand Caravan with 180,000 miles that exhibits stumbling on cold starts occasionally, this started happening at about 100K....figured out it was dirt/soot around the edges of the butterfly valve. It's an easy fix, wet a rag with rubbing alcohol, open the butterfly valve, wipe everything down until it's clean. Stumble is gone! The stumble comes back somewhere between 6 months and a year.

I just put the Vararam velocity stack in my Av two days ago, it's a year and three months old and has 9000 miles on it. The inside of the throttle body already had some light black soot in it. I would not have expected this already. It leads me to believe the Av's design must be prone to getting dirty so I'll be cleaning it at least once a year also!