Throttle body cleaning

I'm thinking about cleaning my throttle body and after searching past threads had a few questions.

1. I believe BNaylor once posted that the MAF sensor should be removed because it can be damaged by the throttle body cleaner. What about the TPS and IAC? Are they safe to be sprayed with throttle body cleanear or do they need to be removed also?

2. How do you clean the MAF sensor? Do you spray it with MAF cleaner and let it drip dry?

3. Does the throttle body need to be removed to effectively clean it? Can you really get to the gunk on the other side of the butterfly valve?

4. I believe the IAC and EGR both have pintles that can be cleaned. Is that effective/worthwile?

I prefer to remove all the sensors so that the passages can be cleaned. Removing the throttle body makes it easier to clean as well as a more complete clean.
As far as the MAF, it is better to use a MAF specific cleaner for the sensor. Some cleaners can actually cause harm.
Same goes for throttle body, get a throttle body specific cleaner.

jsnevets, I hope you don't mind if I add a question to your list as I'm getting ready to do a throttle cleaning myself...

How necessary is it to torque the bolts when you put the throttle back on? Or are you fine do it by hand?

It is always a good practice to torque the bolts on any application especially if you're are using a new gasket, however I have done many of these just hand tightening them, within reason, with a 1/4" drive set.
If you want to torque it to spec's, get the values through your repair manual or perhaps the autozone repair guides may be of assistance.

When you use MAF spray cleaner like CRC brand just let it drip and air dry first before reinstalling. On the IAC the part that really needs cleaning is the spoon at the end of the pintle. See pic. That is the part that carbons up possibly causing idle high IAC count issues. You can use carb or MAF cleaner on the IAC. Lube the spring loaded pintle with 3M brand 3 in 1 oil or similar. Same for the spring loaded EGR pintle.

The TB nuts are torqued to 89 in-lbs if you decide to remove the throttle body on either the L67 or L36 engines.


http://i5.photobucket.com/albums/y186/lizzywiz/iac_2.jpg

Oh sh*t. I hate when these projects get bigger on me. As you can see in the picture below the bolt for IAC sensor broke off. I hope one of those extractor tools will do the job. Also, when I removed the vaccum hose it was so brittle it just broke in half. I was also wondering about the TB cleaner because the label says not to use on vehicles equipped with superchargers. At least the IAC looks clean now. It was completely carboned up. I was also wondering about the intake manifold. It has a lot of buildup. Are you supposed to try and clean that or just the TB?

http://i136.photobucket.com/albums/q197/jsnevets/IMG_3886copy.jpg

http://i136.photobucket.com/albums/q197/jsnevets/IMG_3885copy.jpg

http://i136.photobucket.com/albums/q197/jsnevets/IMG_3887copy.jpg

http://i136.photobucket.com/albums/q197/jsnevets/IMG_3888copy.jpg

http://i136.photobucket.com/albums/q197/jsnevets/IMG_3890copy.jpg

Nice job on the iac!

It looks like you might have enought room to grab that half of bolt with a small vice grips.

Soak it with PB blaster for an hour or so, and try to wrench it out with some vice grips.

I am not sure how those extractors work, but i dont know if they will be small enough.

Worse comes to worse you can just replace the throttle body.

See this is why I just get throttle body cleaner and towel and spray around the throttle butterfly while opening it and spray up into the hole for the IAC. Most often that does the job. It's not necessary to clean out the inside of the intake or plenum or the IAC usually. The idea is the throttle apeture is very small and any gum film around the throttle is very restrictive (compared to the rest of the intake or even the IAC which usually gets cleaned enough anyway by spraying up into the IAC feed hole) when starting and idling and this can make for harder starting and funny idle and off idle performance.

UPDATE. Using vise grips I ended up mushing what was left of the bolt. Then I went from bad to worse trying to use an extractor (probably not exactly the right size) and broke off the tip in the bolt. I thought I was pretty much hosed then. However, I luckily work at a place with a manufacturing machine shop. One of the machinists was able to drill out the core and remove what was left of the bolt. The threads were damaged so he then then drilled and tapped for a 10-32 bolt. It's got mismatched bolts now but who cares. It's back on and working!!

http://i136.photobucket.com/albums/q197/jsnevets/IMG_3897copy.jpg

http://i136.photobucket.com/albums/q197/jsnevets/IMG_3900copy.jpg

Nice! If it were mine, I'd be half tempted to have him re tap the other side so both are the same bolt size.