Gas Pedal Sticks Going Down

[orviskid]

anyone have this issue, 2nd time since owning the truck. you can't push the gas pedal down. you can't just ease into it, you have to punch it to get it to go. when it first happened the dealer replaced some little piece, something with the throttle, the truck has 120k and i'm surprised the same thing is happening again.nothing to spray, you can't see squat under the hood.

[asilverblazer]

Clean the throttle body, espeecially the throttle blade and where it touches around the sides.

 

***EDIT*** Take the big black tube (air intake) off the throttle body to gain access to it.

[superjim]

^^^^^^^

What he said.

Clean the throttle body.

[orviskid]

whats do i use, gum out???

[Draenor]

That would work. I use "enter name brand" TB cleaner and a tooth brush. This gets the caked on carbon off. Then I go back and use a rag to clean it all up. If your really anal, I take the TB off and thoroughly clean the back side out.

[Stylous]

When you do the throttle body, clean the MAS and intake tube as well.

 

Go to Kragen and buy TBC cleaner AND MAS cleaner. They are formulated differently.

 

I disconnect the MAS and hit it with the MAS cleaner...DO NOT TOUCH or SCRUB those wires in there. Just soak it with the MAS cleaner then set it aside to dry. Hit the connection points on the MAS unit and wiring harness as well.

 

Disconnect the rubber intake tube from the throttle body. Hit the tube with TBC cleaner (it's cheaper) to get all that crap out of there as well. Place it to the side and let it dry.

 

Hit the throttle body with the TB cleaner especially where the plate pivots. Move it back and forth with your left hand using the throttle cable pulley. Clean it as good as you can. Hit the plate, the linkage and the body. Also hit the pulley as it will most likely have dirt/crud on it as well. Let it dry.

 

Wait about 15 mins for the TB to dry then put it all back together again.

 

I do this service when I clean my K&N air filter. You're there, why not just do it all at one time. It takes all of 45 mins to do everything.

[qualicas]

Hey, search actually works. My gas pedal is sticking very slightly just when I step on the gas pedal. Couldn't figure why then I read the solution and remembered that I just changed the water pump and had to remove the air tube to the throttle body. Must have gotten some dirt in there.

Darn, and I was looking for an excuse to order a new truck!

[c4cruiser]

There was a TSB out some years ago about sticky TB's

 

It was discussed in this thread and probably others.

 

 

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