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What are those things on top of the valve cover

Emerscape

NAXJA Forum User
Location
Boston, MA
Sorry this may be a simple question - what are the two rubber things called that come out of the top of the valve cover and connect to the airbox and intake. I've noticed one of mine is kinda loose and shows a little fluid around it (nothing really leaking). could this be causing the whisteling noise that I've been hearing?
 
Grommets.
The large one on the front is for fresh air, the smaller one on the back is the CCV grommet to vent crankcase gasses. You need those. They sell them at NAPA. some one has the P/N.
 
Hey Pete,
The are ccv grommets as mentioned above, original part number 2946079.
I'd try removing them and cleaning the area around it...but they're cheap little grommets less than $4 each. I doubt you'd hear a whistle from there, but you never know.
You might have an intake gasket or another type of vacuum leak if you're hearing a whistling...
 
thanks. yeah everyone said I probably have a vacuum or intake gasket leak. Havent had a chance to get ahold of a propane torch to search for the leak. My brother mentioned I could spray carb cleaner or something on the vacuum lines to find the leak. Any truth to this?
 
thanks. yeah everyone said I probably have a vacuum or intake gasket leak. Havent had a chance to get ahold of a propane torch to search for the leak. My brother mentioned I could spray carb cleaner or something on the vacuum lines to find the leak. Any truth to this?

be careful spraying solvents like that around a running engine, especially near the exhaust manifold. a very light shot of carb cleaner will make the RPMs jump up if you do have a vacuum leak. just short shots around where the vacuum lines connect to eachother and the intake manifold will work, and inspect the long plastic vacuum lines for small cracks.
 
been wonder about this myself. I think i have leaks on both the grommets so by buying new ones will this stop the leak? when i did the valve cover gasket i took those houses out and cleaned them. Thought they were good to go but they are leaking now.
 
thanks. yeah everyone said I probably have a vacuum or intake gasket leak. Havent had a chance to get ahold of a propane torch to search for the leak. My brother mentioned I could spray carb cleaner or something on the vacuum lines to find the leak. Any truth to this?

If you can hear it, then it is easy to find with a piece of hose/tubing. I like vinyl tubing, about 3' piece 1/2" or larger.

Stick one end of the tubing in the ear of your choice (preferably one of your ears) and then move the other end around in the engine compartment until you isolate the source.
 
been wonder about this myself. I think i have leaks on both the grommets so by buying new ones will this stop the leak? when i did the valve cover gasket i took those houses out and cleaned them. Thought they were good to go but they are leaking now.

They dry out and shrink over time. For the CCV system to function properly you should replace both grommets. As stated before, the front is for filtered fresh air intake, and the rear is for vacuum from the intake manifold. Also, be sure the orifice in the rear valve cover and the intake manifold vacuum source are not plugged up.
 
thanks guys for being so patient with me. I know I've posted about this a million times (vacuum leak) but I haven't had the ability to chase it down. Thanks again
 
Seen one where the fresh air tube was collapsed and it was wistleing came from the oil cap seal oscilating as air was sucked in there.

On the 96-up I'd caution you on trying to remove them unless you want to replaced them. The rubber grommets harden and then usually the plastic part breaks when you try to get them out. If you do want to get both grommets and fittings, it will save you time/headache.
 
Try the "stogie" test.

Buy a cheap cigar ($1.00), fire it up, toke on it (inhaling not necessary). Take a vac line off and blow smoke into it. If smoke comes out where it shouldn't, you've found your leak(s). Sounds weird, but it WORKS.

Smoking can be hazardous to your health...etc., etc.
 
Try the "stogie" test.

Buy a cheap cigar ($1.00), fire it up, toke on it (inhaling not necessary). Take a vac line off and blow smoke into it. If smoke comes out where it shouldn't, you've found your leak(s). Sounds weird, but it WORKS.

Smoking can be hazardous to your health...etc., etc.

Note: this can be illegal in some states, depending on how old your XJ is. The use of tobacco products by those XJs less than 18 years old is prohibited. :nono:
 
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