Throttle Body Question

[Seamus McBundy]

After removing the intake resonator box, I notice a hissing noise coming from the opening of the throttle body. Is this normal or does this mean I need a new throttle body or gasket?

Thanks,

 

[accuratehorn]

Your car sucks. But relax, all cars suck air into the engine through the intake manifold, preceded by the throttle body. The air cleaner plastic tubing and box is carefully engineered as a sound deadening device, so you normally don't hear all that noise. If part or all of it is removed, or replaced by one of those aftermarket intake systems, you will have a lot of intake noise.

 

[Seamus McBundy]

Thanks. It was shaking pretty good and I couldnt find any vacuume leaks on any of the hoses, checked the plugs and coil packs and they were fine. Then checked the TB mounting bolts and two were loose and that stopped the shaking. Its still a bit rough on idle and seems to hesitate so I wondered if I needed a new TB gasket or of the hissing was normal when the TB plate is closed.

 

[accuratehorn]

Well, it could need a new gasket, and it is in the service manuals to put a new one on there if you remove the throttle body. Since the bolts were loose, it may have a bad place in the gasket. But there will be intake noise, so I don't know if what you are hearing is normal, or a problem.
You can spray a small amount of carb cleaner spray around the gasket area to see if the engine speed changes, which would indicate a leak at that spot. Don't spray it on a spark producing item, though. It is possible to catch fire while doing this. Don't ask me how I know this fact.

 

[Seamus McBundy]

 

[HornBud]

Nothing sucks except for OU. Any movement of air or liquid from one location to another is either a function of gravity or differing air pressures. The most common and easiest to understand example of this is drinking through a straw. You aren't actually pulling the liquid into your mouth. You are lowering the air pressure inside the straw, outside the straw is still 15psi, and the weight of the liquid combined with the air pressure is pushing that cold refreshing beverage into your mouth. Vacuum cleaners work the exact same way...except that, with rare exceptions, nothing is actually going into your mouth.

Therefore, except for OU, everything pushes or falls.


edited to be more clear, I was in a hurry at work

 

[Seamus McBundy]

Your ideas intrigue me and I wish to subscribe to your newsletter.

 

[NCAAFBALLROX]

Accurate is on track; I have a 5.7 Vortec & added a K&N "Cold Air Kit" (also called an "FIPK" for Fuel Injection Performance Kit).

The noise level went up appreciably but I don't notice it now, what with my rumbly dual exhaust going straight back.