29 replies to this topic

[jaslo]

Hi everybody, on my silverado, it seems the gas pedal wants to stick once I first press it idle. Just wondering if anybody else has experienced this? And what is the cure?

[99Silver6.0]

Yup. Take off your throttle body and clean it. Most likely there will be a nasty brown film all over the back side of it. This is from the wonderful PCV setup on the engine. Tends to suck up a bit of oil and send it through the intake. You can also clean inside the intake with some 3M Throttle Body/Intake CLeaner. It will be dirty too.

[jaslo]

I dont think its from the throttle body, because I pressed the gas pedal with my hand and looked underneath the dash and that is where it seemed to be sticking is somewhere underneath the dash.

[Shaners]

About 95% of the time, it tends to be a dirty throttle body.

Pop the air intake hose off and take a look...

I know it feels like it's in the peddle, but it's actually the plate sticking in the throttle body.

[REDZ-71]

I thought it was the pedal too. but it turned out to be the throttle body.
After I took it apart and cleaned it did not stick anymore, and it seams a little bit more powerful.

[derek_silverado]

Maybe I'm missing how the throttle body being dirty makes the pedal stick.

On mine, when you press the gas it seems there is a little resistance and then the resistance does away and I end up squatting the rear or spinning (if I'm on crappy terrain).

Are you guys talking about it sticking open, or being hard to press?

[chevy-guy]

I know that it might sound strange but it is your throttle body, I had the exact same problem as you and it took me about 10 minutes to fix the problem. My gas pedal seemed to feel sticky when I went to take off from idle but after I took the short time to clean, it now it's as smooth as silk, it's not sticking at all! Give it a try and let us know how you make out!

[Shaners]

Are you guys talking about it sticking open, or being hard to press?

If it's hard to press and then all of a sudden it frees up, then it is the throttle body needing cleaned.

[quackmaster]

is there any certain process or certain steps that you need to know about to clean a throttle body? I get a little nervous when I start monkeyin' around with something like that which i've never tinkered with before.

[silverado man]

is there any certain process or certain steps that you need to know about to clean a throttle body? I get a little nervous when I start monkeyin' around with something like that which i've never tinkered with before.

All you need to do is go to the auto parts store grab a can of throttle body cleaner. Go home take the air intake hose off open the butterfly valve give the whole thing a good coat of cleaner take a rag and clean it off you might need to spray a few more time because I'm sure the inside of your throttle body will be full of nasty black stuff. Oh and make sure that you give the butter fly valve a good coat on the joints so that it is lubed up good.

[quackmaster]

is there any certain process or certain steps that you need to know about to clean a throttle body?  I get a little nervous when I start monkeyin' around with something  like that which i've never tinkered with before.

All you need to do is go to the auto parts store grab a can of throttle body cleaner. Go home take the air intake hose off open the butterfly valve give the whole thing a good coat of cleaner take a rag and clean it off you might need to spray a few more time because I'm sure the inside of your throttle body will be full of nasty black stuff. Oh and make sure that you give the butter fly valve a good coat on the joints so that it is lubed up good.

THanks silverado man

I come up to NE Kansas and chase deer around in the fall, you hunt any around up there?

[Jeremy WI]

A TSB out on this one
Increased Accelerator Pedal Effort, Idle Instability (Clean Throttle Body and Adjust Blade) #02-06-04-054B - (03/17/2003)

Increased Accelerator Pedal Effort, Idle Instability (Clean Throttle Body and Adjust Blade)
1999-2002 Chevrolet Silverado

2000-2002 Chevrolet Suburban, Tahoe

2002 Chevrolet Avalanche

1999-2002 GMC Sierra

2000-2002 GMC Yukon, Yukon XL

with 4.8L or 5.3L V8 Engine (VINs V, T, Z -- RPOs LR4, LM7, L59)

This bulletin is being revised to add condition information. Please discard Corporate Bulletin Number 02-06-04-054A (Section 06-Engine).

Condition
Some customers may comment on an idle instability and/or a higher than expected accelerator pedal effort from the idle position.

Cause
Condition may be caused by deposits in the throttle body bore and on the throttle plate.

Correction

Important
This procedure only applies to cable actuated throttle bodies on the models listed above. This procedure should not be performed on electronically controlled throttle bodies or on any vehicle or engine that is not listed above in the Models section.


Verify that the cause for this condition is not a damaged or binding throttle cable.
Remove the air intake duct. Refer to Air Cleaner Duct Replacement.
Inspect the vehicle for installation of a fixed orifice PCV valve, refer to Corporate Bulletin Number 01-06-01-029B for PCV valve identification. Vehicles undergoing this throttle body procedure MUST use a Fixed Orifice PCV Valve, P/N 12572717.
Clean throttle body bore and throttle valve plate of carbon using a shop rag and an appropriate cleaner. Refer to Engine Controls Repair Procedures - Throttle Body Cleaning Procedure.
Select the correct plug for the size of the air bypass hole in the throttle body being serviced. Use a 1/8-inch (.125") drill bit to determine which plug to use.
Vehicles built before introduction of the Fixed Orifice PCV Valve will have a 3.75 mm (.150") air bypass hole in the throttle plate. The 1/8-inch drill bit is smaller than the air bypass hole in these throttle bodies and can be inserted into the bypass hole. To plug the air bypass hole in these vehicles requires the yellow plug, P/N 12580749.
Vehicles built after introduction of the Fixed Orifice PCV Valve will have a 2.6 mm (.104") air bypass hole in the throttle plate. The 1/8-inch drill bit is larger than the air bypass hole in these throttle bodies and cannot be inserted into the bypass hole. To plug the air bypass hole in these vehicles requires the red plug, P/N 12581011.

Insert the appropriate plug (1) into the air bypass hole in the throttle plate. Insert the "tail" end of the plug through the throttle plate air bypass hole.

Open the throttle plate to allow access to the tail end of the plug. Pull the tail section to securely position the plug into the air bypass hole and trim excess material (1) from plug.
Turn ignition key to the on position, with engine off.
Use the Tech 2 Scan tool to read initial TPS voltage.

Important
TPS voltage cannot exceed .69 V. If the vehicle has an initial TPS voltage greater than .61 V, replace the Throttle Body Assembly. This part is currently on parts restriction. Contact the General Motors Powertrain Quality Center at 866-654-7654 for assistance.


Using the Tech 2 Scan tool and a T15 driver to rotate the Minimum Air Rate screw, increase TPS voltage by .08 Volts (Refer to TPS Voltage Chart below).
Turn ignition key to the off position. Verify that the accelerator pedal moves freely - Depress the accelerator pedal to the floor and release.
Install the air intake duct. Refer to Air Cleaner Duct Replacement.
Start engine.
Using the Tech 2 scan tool, monitor TPS voltage and verify the TPS voltage is no greater than 0.69V.
Road Test Vehicle.

Important
If an increased accelerator pedal effort condition still exists after performing this bulletin, throttle body replacement may be required. Please contact the General Motors Powertrain Quality Center at 866-654-7654 for assistance, as the throttle body is currently on a parts restriction program.

If initial TPS voltage is greater than .61 V Replace Throttle Body Assembly

Parts Information



Part Number 12580749
Description Plug, Throttle Plate - Yellow
Qty 1

Part Number 12581011
Description Plug, Throttle Plate - Red
Qty 1


Parts are currently available from GMSPO.

[silverado man]

is there any certain process or certain steps that you need to know about to clean a throttle body?  I get a little nervous when I start monkeyin' around with something  like that which i've never tinkered with before.

All you need to do is go to the auto parts store grab a can of throttle body cleaner. Go home take the air intake hose off open the butterfly valve give the whole thing a good coat of cleaner take a rag and clean it off you might need to spray a few more time because I'm sure the inside of your throttle body will be full of nasty black stuff. Oh and make sure that you give the butter fly valve a good coat on the joints so that it is lubed up good.

THanks silverado man

I come up to NE Kansas and chase deer around in the fall, you hunt any around up there?

No I never really got into hunting but I did grow up on a farm though. Where do you go hunting at? I'm originally from Baileyville (Nemaha County). My dad use to rent out his land to hunters.

[RyanZ71]

Mine is starting to stick a little bit as well, I am going to give that procedure a try. Thanks for the info everyone!

[jaslo]

Just wondering if you guys have a detailed procedure on how to clean out the throttle body? Also has anyone have taken their truck back to the dealership to get the procedure done?