First Look Inside Throttle Body

SSTJ

SSTJ

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Removed my airbox and had my first peek inside the throttlebody of my 97 2.5. Is this black stuff anything to worry about or check on?

It’s oily, and smears when I rub it.

image.jpg


Update: Learned in this thread that I should clean this with throttle-body cleaner and a rag, preferably while the engine is running. Then, some good tips in this thread about how to clean out the idle air controller (IAC) at the same time, by spraying throttle-body cleaner into the IAC cutout in short bursts, and while engine is idling. Also found this video very helpful.
 
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I'm no expert but I'm pretty sure that is normal to get some oil in the air intake/throttle body.
 
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That's 100% normal, it's just blowback from the combustion chambers. Clean it with some throttle body cleaner and a rag and it'll be fine. I like to clean it while the engine is running, makes it easier to do and IMO it does a more thorough job.

If you do that, make sure to also spray 25-30% of the can into the throttle body while the engine is at IDLE (no faster) rpms. When the engine is at idle rpms it'll suck the cleaner in through the IAC (idle air control) module which is what the engine gets all its air through when the engine is idling. The IAC gets dirty and causes a bad/rough idle so make sure to clean the IAC as mentioned.
 
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Jerry Bransford said:
That's 100% normal, it's just blowback from the combustion chambers. Clean it with some throttle body cleaner and a rag and it'll be fine. I like to clean it while the engine is running, makes it easier to do and IMO it does a more thorough job.

If you do that, make sure to also spray 25-30% of the can into the throttle body while the engine is at IDLE (no faster) rpms. When the engine is at idle rpms it'll suck the cleaner in through the IAC (idle air control) module which is what the engine gets all its air through when the engine is idling. The IAC gets dirty and causes a bad/rough idle so make sure to clean the IAC as mentioned.
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when i first purchased my lj,i took the manifold off and sandblasted the oxidation off and cleaned out the runners and took the throttle body apart and cleaned out the sensor areas etc...funny,it ran fine before and after but it looks better and i dont guess im gonna have to do all that again for awhile!
 
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Jerry Bransford said:
That's 100% normal, it's just blowback from the combustion chambers. Clean it with some throttle body cleaner and a rag and it'll be fine. I like to clean it while the engine is running, makes it easier to do and IMO it does a more thorough job.

If you do that, make sure to also spray 25-30% of the can into the throttle body while the engine is at IDLE (no faster) rpms. When the engine is at idle rpms it'll suck the cleaner in through the IAC (idle air control) module which is what the engine gets all its air through when the engine is idling. The IAC gets dirty and causes a bad/rough idle so make sure to clean the IAC as mentioned.
Click to expand...

Nice, thanks. I'll do just that. Any favorite brands for throttle body cleaner?
 
Jerry Bransford said:
If you do that, make sure to also spray 25-30% of the can into the throttle body while the engine is at IDLE (no faster) rpms. When the engine is at idle rpms it'll suck the cleaner in through the IAC (idle air control) module which is what the engine gets all its air through when the engine is idling. The IAC gets dirty and causes a bad/rough idle so make sure to clean the IAC as mentioned.
Click to expand...

Hey Jerry,

Thanks again for this tip. Any benefit of taking your suggested approach over this approach? Both are simple so I can just do both of course, but thought I'd ask in case there's something to learn here.
 
Jerry Bransford said:
That's 100% normal, it's just blowback from the combustion chambers. Clean it with some throttle body cleaner and a rag and it'll be fine. I like to clean it while the engine is running, makes it easier to do and IMO it does a more thorough job.

If you do that, make sure to also spray 25-30% of the can into the throttle body while the engine is at IDLE (no faster) rpms. When the engine is at idle rpms it'll suck the cleaner in through the IAC (idle air control) module which is what the engine gets all its air through when the engine is idling. The IAC gets dirty and causes a bad/rough idle so make sure to clean the IAC as mentioned.
Click to expand...

Thanks again Jerry. Did this today, finally. I did it in short bursts (as short as I could push down hard enough to get a good mist instead of a few droplets). The RPMs dropped each time, which makes sense I guess. Twice it stalled, but then fired back up fine.

Just curious, but if I were to aim the spray right into the IAC cutaway, could I open the throttle a little bit with my other hand, just to make the process go more smoothly?
 
Ok, now I’m curious. Is it a valve or isn’t it? Should I clean it with throttle-body cleaner or shouldn’t I?
 
It's a piece of plastic with a "metered hole" in it. No moving parts, like a regular PCV valve, but I have seen them get coked up with old oil. Wouldn't hurt to spray some carb cleaner through it.
 
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