Throttle Body leak(s)

EJD

EJD

TJ Overlander
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So I was on the hunt for vacuum leaks and performed a smoke test the other day. While I didn't find any leaks coming from any hoses or fittings yet but I was getting smoke coming out of the area of the Throttle Body where the Throttle itself goes into the Body. I was also getting smoke coming out of the TPS sensor.
 
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Sorry pic is upside down.
jinaxe.jpg

Center of picture where the throttle itself (unless its called something else, the "rod" with the spring wrapped around it hooked to the cable) goes into the Body, is where i'm getting smoke coming out of during my smoke test.

bfp3.jpg
 
Anyone have any thoughts on either of these leaks? Is there a seal on the inside of the throttle that can be replaced or upgraded?

Is the TPS not bolted in all the way, or a bad seal on that? Would these sorts of leaks on the TB cause a stall?
 
I'm not 100% sure, but I think that is normal. I don't think that's supposed to be 100% airtight there.

I could of course be wrong, so I'll wait until someone more knowledgable responds.

I though the brake booster fixed your stall, no?
 
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Chris said:
I'm not 100% sure, but I think that is normal. I don't think that's supposed to be 100% airtight there.

I could of course be wrong, so I'll wait until someone more knowledgable responds.

I though the brake booster fixed your stall, no?
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The new Brake Booster did fix the stall but I wasn't sure if I maybe still had a small vacuum leak here that needed attention. So I figured i'de post it and see if anyone had any insight on the anatomy and airtightness of the TB.
 
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EJD said:
The new Brake Booster did fix the stall but I wasn't sure if I maybe still had a small vacuum leak here that needed attention. So I figured i'de post it and see if anyone had any insight on the anatomy and airtightness of the TB.
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Makes me want to go test mine. But I'm sure that it can't be 100% air tight... At least I don't think so. Unless you have symptoms of a vacuum leak, then I would say you're fine.
 
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I actually think it does idle ok maybe a touch low not high, however it feels like it has a delayed acceleration sometimes like when you hit the gas pedal, see the rpms go up, but the Jeep physically is not moving at the same pace as the rpms say. Then it engages after a brief delay, if that makes sense...

I just always thought there was some kind of leak.
 
EJD said:
... however it feels like it has a delayed acceleration sometimes like when you hit the gas pedal, see the rpms go up, but the Jeep physically is not moving at the same pace as the rpms say. Then it engages after a brief delay, if that makes sense...
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When is the last time you checked your automatic transmission's ATF level? Low ATF can cause that exact problem. And does that happen only after it has been sitting a long time, like overnight or does it happen throughout the day?

Keep in mind that your engine MUST be running and your 32RH transmission MUST be in Neutral while you are checking the ATF level via the transmission's dipstick. If those two conditions are not met, you'll get an erroneous ATF level. If you do need ATF, make sure to only add ATF+4. It's not the right stuff if it doesn't say ATF+4 in big letters on the front label.

My son was having transmission problems, it finally just stopped working. I kept telling him that about his automatic ATF level, that the engine has to be running & in neutral before he'll get an accurate indication of the ATF level. He kept saying 'yeah I checked it like you said' but several months went by with transmission problems and after I pushed him, he said 'yeah I checked it right after shutting the engine off & it was still warm'. After he got an earful from me, he started the engine and checked its level, it was nearly 4 quarts low. His transmission is working perfectly since he got the ATF level up to where it needed to be. It also took another earful for him to finally understand he couldn't just add just any ATF. Damned kids never seem to listen.
 
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Jerry Bransford said:
When is the last time you checked your automatic transmission's ATF level? Low ATF can cause that exact problem. And does that happen only after it has been sitting a long time, like overnight or does it happen throughout the day?
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It does usually only happen after its been sitting a while or overnight type situation...once its been driving for a bit it doesn't really happen.
 
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Jerry Bransford said:
Keep in mind that your engine MUST be running and your 32RH transmission MUST be in Neutral while you are checking the ATF level via the transmission's dipstick. If those two conditions are not met, you'll get an erroneous ATF level. If you do need ATF, make sure to only add ATF+4. It's not the right stuff if it doesn't say ATF+4 in big letters on the front label.

My son was having transmission problems, it finally just stopped working. I kept telling him that about his automatic ATF level, that the engine has to be running & in neutral before he'll get an accurate indication of the ATF level. He kept saying 'yeah I checked it like you said' but several months went by with transmission problems and after I pushed him, he said 'yeah I checked it right after shutting the engine off & it was still warm'. After he got an earful from me, he started the engine and checked its level, it was nearly 4 quarts low. His transmission is working perfectly since he got the ATF level up to where it needed to be. It also took another earful for him to finally understand he couldn't just add just any ATF. Damned kids never seem to listen.
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I have to say, i'll be damned!

See I have (what I thought) checked the ATF not that long ago and it actually seemed high, level was OVER the max fill line by a little. What I didn't do before that you just mentioned was check the fluid with the TJ in "neutral" vs in park. I did not realize that was the key to getting an accurate reading and let me say...wow it was low. Like the bottom of the "low" zone on the dipstick.

I actually had an extra quart of Mopar ATF+4 laying around from my Transfer Case fluid job, so I added a little at a time through the dipstick neck and it took the whole quart and that brought it up to the bottom edge of the "ok" area on the dipstick itself. I bet it would take another 16-32oz or more to fill up the whole OK area and maybe touch the max line. Is that worth adding a bit more?[/QUOTE]
 
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Yes it's worth bringing it up to the top of the full line. Many of us overfill our automatic transmissions to insure it doesn't suck air on a steep climb and act like you shifted into Neutral... which is darned scary when it happens, since it invariably happens when at the steepest/hairiest part of a climb.

And yes, 2002 and older TJs use the 32RH or 30RH automatic transmissions and they must be in Neutral, not Park, to check their ATF level. Only the 42RLE automatic used in 2003 and newer TJs can be checked in Park or Neutral.
 
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