sucking air between engine and transmission

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Krill

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after having injectors replaced my 2011 LR4 with 195,000 miles is having issues idling with the A/C off. if A/C is on it idles fine. I found that the car is sucking air from that little drain hole/vent between where the engine and transmission meet up. anyone ever had an issue like this or can shed some light on it?

see video
 

Cthehentz

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Vacuum leak, with ac on the engine will idle higher keeping the engine running.
 

Krill

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Vacuum leak, with ac on the engine will idle higher keeping the engine running.

Yes but vacuum leak through the rear main seal or what? No oil leaks( car sat for 3 weeks while I was on vacation and not a single drip on the floor) could it be something as simple as replacing the Pcv intake valves on the passenger valve cover?
 

Krill

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If I knew it wouldn’t damage anything I’d seal that hole so no water or mud got sucked up while driving
 

Krill

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what could be used to seal that puppy? epoxy?

I have an aviation fuel tank sealer called Pro Seal that would work on it but if its an issue id like to fix it instead of put a bandage on it. just don't understand what is creating such a vacuum. if I open the oil fill cap it sucks a huge gulp of air in and stops sucking from the bottom. is it normal to have a lot of suction through the oil cap?
 

Cthehentz

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I have an aviation fuel tank sealer called Pro Seal that would work on it but if its an issue id like to fix it instead of put a bandage on it. just don't understand what is creating such a vacuum. if I open the oil fill cap it sucks a huge gulp of air in and stops sucking from the bottom. is it normal to have a lot of suction through the oil cap?

Any codes? Engine miss?
 

avslash

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Without crawling under my truck, I'm trying to visualize exactly where you are pointing to in the video.

Is that the bottom flange of the bell housing, immediately behind the oil pan?

When I think vacuum leak, I general think intake side, but in looking at pictures I can't find a point where a leak would pull vacuum on the bell housing space, which in turn leads me to think rear main seal, as mentioned in your initial post.

Is there an inspection port on the bell housing, or could you get a borescope in there if you remove the starter? I'm wondering if you could detect evidence of oil leakage around the rear main.

Looking around on other forums, I did find mentions of a leaking rear main seal causing idling issues. In one case it was linked to bad crank case vents.

I think my first course of action might be to change those vents and see if it did any good. as I'm assuming changing a rear main involves a lot of work that i don't want to think about. I'm wondering if you could get the trans far enough back to do it by dropping the transfer case, or if you would have to pull the whole block.
 

scott schmerge

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Without crawling under my truck, I'm trying to visualize exactly where you are pointing to in the video.

Is that the bottom flange of the bell housing, immediately behind the oil pan?

When I think vacuum leak, I general think intake side, but in looking at pictures I can't find a point where a leak would pull vacuum on the bell housing space, which in turn leads me to think rear main seal, as mentioned in your initial post.

Is there an inspection port on the bell housing, or could you get a borescope in there if you remove the starter? I'm wondering if you could detect evidence of oil leakage around the rear main.

Looking around on other forums, I did find mentions of a leaking rear main seal causing idling issues. In one case it was linked to bad crank case vents.

I think my first course of action might be to change those vents and see if it did any good. as I'm assuming changing a rear main involves a lot of work that i don't want to think about. I'm wondering if you could get the trans far enough back to do it by dropping the transfer case, or if you would have to pull the whole block.

I too would think failed ccv. I would avoid any type of sealing. That gap between bell housing and engine is there for a reason- my guess is to drain water ingress to the torque converter on wading...or when your rear main seal gives up the ghost, oil... Sealing it without finding the cause of the vacuum would in my uneducated opinion might be a mistake.

Just my .02 for what it’s worth. Let us know what you find
 

ktm525

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edit. My previous answer was wrong. I thought it was blowing not sucking. A PCV releases pressure so it allows the system to "blow" if over pressured. Sucking? Not sure.

Did you mess with the heads? It sounds like an air leak between the valley and the intake (ie. bad intake gasket seal).
 
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