Thoughts On Cleaning Throttle Body

[914lps]

I am thinking about cleaning the Throttle body on my 91 LS. I want to do it with it on the car. I know how to take all the stuff off to get to the throttle body opening. I figure spray cleaner should work. Both with the engine running and not. But this is were I would like your 2 cents worth. I know doing it off the car is best but I'm not willing to do that much work to take it off (at this time). If it matters plug are new.

I have heard never use Carb cleaner, only Throttle Body cleaner... Is there really a difference. Booth are marked as safe for O2 Sensors and cats.

I have heard not to do it on the car, as you just wash everything down to your valves and plugs and foul them up???

Your thoughts??

I have a 400 mile drive coming on Monday. I figure clean the TB (Monday morning just before I'm leaving), then hit the road and drive for 400 mile straight (non-stop at 65 to 85 mph) with a extra bottle or two of fuel system cleaner added to the tank of gas (Like chevron or other major brand). I figure this will clean everything out... Again, kind folks your thoughts on this?

[maxed_out]

hey 914lps. If it was me and time was short, I'd use seafoam. Use the Spray can to do the TB-like the day before. hey if you got no time I understand.... Theres nothing like cleaning the tb with it off.

Use the seafoam liquid before you go.... Get down to about a 1/4 tank o gas and add 1/2 can of seafoam to gas tank. Add the other half to the crankcase. Drive. See if you notice anything like I did.

Theres pretty good directions on-line for the seafoam. There's a couple variations on applications. My 91 lex never ran better. My 90 Camry with 270k is doing 32 mpg because of the stuff.

[TexasLexus94]

I've used the spray and additive cleaners, but you can't beat stripping off the Mass Air Flow Sensor and associated connections, and doing a real cleaning into the throttle body. I have an old tooth brush that I tie to a wood extension, and along with spraying throttle cleaner-(doubt if carb cleaner is any worse), you'll be amazed at the amount of black crap you can remove. Doubt if additives and sprays really do that much alone-not as much as elbow grease.

[914lps]

I've used the spray and additive cleaners, but you can't beat stripping off the Mass Air Flow Sensor and associated connections, and doing a real cleaning into the throttle body.  I have an old tooth brush that I tie to a wood extension, and along with spraying throttle cleaner-(doubt if carb cleaner is any worse), you'll be amazed at the amount of black crap you can remove.  Doubt if additives and sprays really do that much alone-not as much as elbow grease.

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I'll take the stuf of the car to get to the opening of the TB , I just do not want to take the TB itself or the top manafold off the car. I want to clean it by spay cleaner onto the opening of the TB with it on the car.

As the TB is in place before the Injectors I know there is no aditive that will clean it or the top manafold area before the injectors.

[obergc]

Here's a link to a procedure for cleaning the TB while still on the car. Worked great, really recommend the Valvoline TB cleaner, TB came out spotless with little effort.

http://www.lextreme.com/tb.htm

[Lexls]

Cleaning it on the car will do something but it's not going to be nearly as good as taking it off. Take the TB off! Yeah, it can look good while it's on the car but seriously, there's more than you realize....take a look at what I found:

Do you really think you could get all that off without removing the TB? NO! If you want to really clean it, take it off. Just my 2 cents.

http://www.lexls.com/tutorials/EFI/throttlebody.html

[914lps]

I have read your how to at www.lexls.com thanks again for the great info. But then again how far in do you clean? What about all that stuff on the inside of the manafold?

[monarch]

Do you really think you could get all that off without removing the TB?  NO!  If you want to really clean it, take it off. 

On other Toyotas I have been able to thoughly clean the throttle plate using this cleaner

http://www.saber.net/~monarch/tpc.jpg a firm bristle toothbrush and some old rags soaked in the cleaner. I have not tried this method on my V8 Lexus yet however.

The scary part of taking the throttle body off is that none of the tutorials covers removal and installation of the throttle cable very well.

[daffy]

hi monarch,

The throttle cable is easy to take off and when reinstalling, just make sure you have somebody step on the gas pedal to the floor to make your adjustment at full throttle. You don't want the cable so tight, that someday it will cause it to break, when you "floor" it. I have done other cars the same way as well as my 1991 LS400 just recently. I totally agree the best way to clean the throttle valve body is to take it right off. Just a warning, don't get any of the cleaning fluid into the electronic areas (beside the throttle plates). I was told this by a mechanic.

Daffy