Throttle Body And Top End Cleaning

whitefish · November 17, 2009

A few years ago I was complaining to a GM Service Manager about a sticky throttle on my 2000 Silverado 4.8l? I can't remember the name of the stuff I bought from him, but I think it was something like 'GM Combustion Chamber Cleaner"? I don't think it was GM Top End Cleaner. Anyways, he recommended to pull the air intake off the TB and to spray in a whole can of the stuff into the TB, washing the TB and throttle plate while holding the throttle open to keep from stalling.

I plan on doing the same for my 2005 and the manager (whom I respect and trust) is retired and not around to ask what to do anymore. So I wanted to know what's the current accepted practice for TB and top end cleaning (never did the later on my 2000). Some of my questions/concerns are....

- What do I use? GM Top End Cleaner, Combustion Chamber Cleaner, Sea Foam Deep Creep....etc?

- Is hydraulic lock a real concern? I sprayed in the whole can of the GM Combustion Chamber Cleaner in my 2000 with no problems other than white smoke. I'm think I sprayed it in all at once rather than in short bursts.

- Is there a TSB on how to do this and with what? I think there was for my 2000.

Thanks

Draenor · November 17, 2009

The only way to really clean the TB is to remove it. Then take off all the sensors and libberally spray it down with TB cleaner. I either scrub it with a old toothbruck or rag to get all the deposits off.

whitefish · November 17, 2009

The only way to really clean the TB is to remove it. Then take off all the sensors and libberally spray it down with TB cleaner. I either scrub it with a old toothbruck or rag to get all the deposits off.

Yeah, I've noticed a few people say that. Is there a "How To" on this? Probably pretty straight forward, but nothing like having some tips and tricks.

Draenor · November 17, 2009

Lets see....

Vehicle is turned off.

Disconnect neg batery cable. ..or your supposed to....

Remove intake from TB.

Disconnect connector from IAT and TPS

Disconect throttle cable or disconnect DBW connector

Remove coolant bypass hoses. (Can get messy)

Remove nuts/bolts holding TB in place.

Remove gasket ,Try not to damage the gasket while the TB is off.

Remove IAT and TPS sensors from TB. (Should be 2 screws for both)(I always kept them in and crossed my fingers)

Spray cleaner and scrub if necessary. Reinstall in reverse.

off the top of my head, that should be the just of it.

whitefish · November 17, 2009

Awesome - what do you use for "spray"? You can't use carb cleaner, right?

peteking · November 17, 2009

Awesome - what do you use for "spray"? You can't use carb cleaner, right?

I use Seafoam's Deep Creep cleaner. (10 bucks at an auto parts store). It worked well when I cleaned up my TB.

bossier62guy · November 18, 2009

A few years ago I was complaining to a GM Service Manager about a sticky throttle on my 2000 Silverado 4.8l? I can't remember the name of the stuff I bought from him, but I think it was something like 'GM Combustion Chamber Cleaner"? I don't think it was GM Top End Cleaner. Anyways, he recommended to pull the air intake off the TB and to spray in a whole can of the stuff into the TB, washing the TB and throttle plate while holding the throttle open to keep from stalling.

I plan on doing the same for my 2005 and the manager (whom I respect and trust) is retired and not around to ask what to do anymore. So I wanted to know what's the current accepted practice for TB and top end cleaning (never did the later on my 2000). Some of my questions/concerns are....

- What do I use? GM Top End Cleaner, Combustion Chamber Cleaner, Sea Foam Deep Creep....etc?

- Is hydraulic lock a real concern? I sprayed in the whole can of the GM Combustion Chamber Cleaner in my 2000 with no problems other than white smoke. I'm think I sprayed it in all at once rather than in short bursts.

- Is there a TSB on how to do this and with what? I think there was for my 2000.

Thanks

Get some throttle body cleaner from you local auto parts store, remove the air intake, open the butterfly and spray the shit out of it. If it's that gunked up use a rag to clean it out. I've cleaned mine a few times like that and it works just fine. No need to go through all of the trouble of removing it. BTW, your 05 shouldn't gunk up like the 00 did.....GM reworked the PCV system somewhat.

whitefish · November 18, 2009

BTW, your 05 shouldn't gunk up like the 00 did.....GM reworked the PCV system somewhat.

Good to know.

Honestly, I haven't pulled the air intake off yet to look at the TB. I've just noticed that the acceleration was kinda sluggish compared to my old 4.8 (2WD) and other 4.8 and 5.3 4WD's I've driven. Has 94,000 miles on it, so it shouldn't really be that tired yet. So far I've just changed the plugs. After I clean the throttle body, I might do a top end treatment (Seafoam) or get a top end/fuel injector cleaning using the canister that hooks up to the fuel rail.

telo · November 18, 2009

A few years ago I was complaining to a GM Service Manager about a sticky throttle on my 2000 Silverado 4.8l? I can't remember the name of the stuff I bought from him, but I think it was something like 'GM Combustion Chamber Cleaner"? I don't think it was GM Top End Cleaner. Anyways, he recommended to pull the air intake off the TB and to spray in a whole can of the stuff into the TB, washing the TB and throttle plate while holding the throttle open to keep from stalling.

I plan on doing the same for my 2005 and the manager (whom I respect and trust) is retired and not around to ask what to do anymore. So I wanted to know what's the current accepted practice for TB and top end cleaning (never did the later on my 2000). Some of my questions/concerns are....

- What do I use? GM Top End Cleaner, Combustion Chamber Cleaner, Sea Foam Deep Creep....etc?

- Is hydraulic lock a real concern? I sprayed in the whole can of the GM Combustion Chamber Cleaner in my 2000 with no problems other than white smoke. I'm think I sprayed it in all at once rather than in short bursts.

- Is there a TSB on how to do this and with what? I think there was for my 2000.

Thanks

Get some throttle body cleaner from you local auto parts store, remove the air intake, open the butterfly and spray the shit out of it. If it's that gunked up use a rag to clean it out. I've cleaned mine a few times like that and it works just fine. No need to go through all of the trouble of removing it. BTW, your 05 shouldn't gunk up like the 00 did.....GM reworked the PCV system somewhat.

Occasionally you may need to remove the TB to do a more thorough cleaning. There is buildup that you don't get by just hosing it off from the outside.

WaterGuy · November 19, 2009

"Occasionally you may need to remove the TB to do a more thorough cleaning. There is buildup that you don't get by just hosing it off from the outside."

Yep, same with me.

I don't have a true schedule to do an "off-truck" cleaning.

It mainly has to do with how bad it looks after so many of the "quickies" and if I have enough beer in the frig for the project.